Sulfur denitrator experiment

[Delphinus]

I've decided to try a sulfur denitrator. I feed my fish generously, so although I do the water changes, do heavy skimming; I tend to run with nitrates.

I had at least two functioning calcium reactors, only one of which I'm running, so I picked up some Caribsea LSM (elemental sulfur beads) and filled the smaller of the two I had (leaving the midsize unit to still run as a calcium reactor).

I guess technically this isn't so much an experiment to see whether a sulfur denitrator will "work" per se (there are enough testimonials to show the theory is sound), in my case it's more an experiment to see if I could use my smaller reactor as an effective remover of nitrate. It's a very small reactor and only holds approx 1/3 of a container of ARM (or sulfur, in this case).

I used the second stage of my midsize calcium reactor, filled with ARM, to buffer the low pH output of the sulfur reactor.

Unit is recirculated with a Mag2 pump, fed by a minijet powerhead in the sump. The output of the first stage is a John Guest style ball valve for 1/4" tubing and that is closed most of the way, in order to produce an effluent drip rate of 1 drop per second.

I put the unit online on Monday evening.

First challenge was trying to find the valve position to create a steady driprate. I find after 24 hours it tends to have slowed, so I might need to adjust the feed pump situation (I'm currently looking for an Aqualifter pump to see if I can produce a more consistent drip rate with that.).

I'm running the unit on my ritteri tank, which, after a recent skimmer problem that I only fixed about a week ago, has rampant nitrates at 75ppm (the anemone can handle it, it's lived in as high as 80ppm in the past .. there are no corals in this tank .. if there were, they wouldn't be for long at that kind of level!! :eek:).

pH in the tank runs about 8.2.

After 24 hours, pH of the effluent had not dropped significantly (8.1).

After 48 hours, pH of the effluent had dropped to 7.8. Tank still at 8.2, so a 0.4 pH reduction already.

After 72 hours, pH of the effluent has dropped to 7.5. Tank still at 8.2.

There is no sulfurous scent to the effluent whatsoever at this point.

My next plans are to, at the one week point, test the nitrate level of the effluent and compare to tank water, to see if there is indeed a reduction.

I also want to test pH before the second stage and compare to the pH after the second stage, to determine how effective the volume of ARM I'm using is at buffering the output of the first stage.

My main concern is to see whether the small volume of media is enough to create the anoxic zone required for the anaerobic bacteria to take hold. Even with a flowrate as slow as 1 drop per second (roughly 10ml/min), I'm concerned this could introduce too much oxygen into the first chamber. Time will tell.

To convert the calcium reactor into a sulfur reactor ... the main difference is you don't inject CO2 into the sulfur reactor. So you need to close off or remove the CO2 injection port. In my reactor it's a T fitting on the pump intake. I decided to leave the "T" in place because I may go back to using it as a calcium reactor and this way I won't lose the T fitting. Instead I just inserted a small piece of tubing with an irrigation dripline plug to cap it off.


Here are some pics:

First stage filled with LSM beads, recirculating; feeding into single-pass second stage filled with ARM.
(The braided hose and green tubing are not related to this reactor. Same for the red tubing, which is my FW topup line...)

http://members.shaw.ca/hobiesailor/aquaria/misc/denitrator1.jpg

A closeup of the feed line into the T, which is capped off on the unused direction (which is ordinarily used for the CO2 feed):
http://members.shaw.ca/hobiesailor/aquaria/misc/denitrator2.jpg

[Psyire]

Nice, I'm in the process of gettings something similar together. (but on a larger scale) Keep us posted!

[christyf5]

Looks good Tony. I'm interested to hear how this pans out :biggrin:

[Joe Reefer]

Cool, what are your initial nitrate readings?

[Delphinus]

The tank I would like to move it to, and keep it on permanently, has 25ppm NO3.

The tank it is currently on, has 75ppm. It shouldn't have gotten that high but ... I guess I've been more or less neglecting that tank lately. :( Ooops, well anyhow I've fixed it's skimmer, I'll kick off a nice big water change soon, but thought I would take advantage of the high nitrates to see if my little experiment here will work. If it knocks the number down from that high a starting point then we know that this is working.

[Farrmanchu]

Don't you need to "seed" the new sulphur media? Thought there was a special bacteria envolved.

[Delphinus]

There is, but my assumption here is that you create the anoxic zone and the culture will develop on its own, much like any other biological filter, or DSB. "If you build it they will come." That's why there is a "cycling" stage to these things.

[reeferaddict]

There is, but my assumption here is that you create the anoxic zone and the culture will develop on its own, much like any other biological filter, or DSB. "If you build it they will come." That's why there is a "cycling" stage to these things.

Yes there IS a cycling time Tony... I bought one in the summer and have been running it ever since with great results... I bought a Korralin 1501 with sulfur media and it took about a month before my nitrates started to drop, but once they did, I have had them at ZERO for over 3 months now. I too feed my overstocked tank generously and best of all... no more $100 a month in salt! :mrgreen:

[Skimmerking]

Tony sounds good. I hope that i can get one if I can figure out this kalk reactor that i have I may have to fix it into a sulphur reactor too. here is a picture of the kalk reactor.. the one on the right what ya think TOny is it workable.
http://i38.photobucket.com/albums/e122/asmodeus338/235%20Gal%20REEF/waterfield009.jpg

[Delphinus]

Potentially .. you might end up needing to modify it quite a bit though. The kalk reactor mix path is from the bottom to about partway up, whereas you'd want to fill as much of the chamber as possible with the media, so the mix path needs to go from the bottom to right to the top. The pump may also need to be upped from a maxijet to something stronger.

I'm by no means an expert on the subject though, I'm just trying this out for the first time just to try to figure it all out too!

[Delphinus]

Day 6 Readings:

Tank pH - 8.2
Tank NO3 - 75ppm (Salifert)

Stage 1 effluent pH - 7.3
Stage 2 effluent pH - 7.6

Stage 2 effluent NO3 - 50ppm (Salifert)

Just to eliminate "testing error" (since I only did one sample for each reading above) I'll test NO3 again tomorrow using a different test kit. The original readings I took, were done with an Elos NO3 test kit, so that's what I'll use again tomorrow to see if I can confirm the apparent reduction already at this point.

Anyhow this is interesting stuff. Just under a week and the effluent coming out of the reactor appears to have a lower nitrate value than the inflow. The second stage, for buffering the low pH output of stage 1, does appear to have some function although not as profound as one might like (0.3 difference? better than nothing I suppose). Really is there a difference between dumping 7.3 into your tank versus 7.6? The drip rate is about 1 drop per 1-to-2 seconds so it is a very slow throughput.

[Psyire]

Nice results so far!

I would think the 2nd stg will work better once the bacteria is established in the sulphur stage... The difference in pH should grow as more and more CO2 is produced by the denitrifying bacteria.

[Delphinus]

Day 10 Readings (Thursday, forgot to post right away)

Tank pH - 8.2
Stage 2 effluent pH - 7.5 (didn't measure stage 1 effluent)
Tank NO3 - 75ppm? 60ppm? Had a REALLY hard time guessing how pink the reading was.
Stage 2 effluent NO3 - Hopelessly unreadable. Seemed like less but cannot be sure.

I hate test kits. :( Going to try again in a few days.

And I broke my vial for the Elos test kit so these were done with Salifert. Did I mention I hate test kits???

[Delphinus]

Unfortunately it's too late and too expensive to ask Santa for one of these, but how cool is THIS thing?
http://www.jlaquatics.com/phpstore/store_pages/details/testkits.php?product_ID=pp-mno3

Um .. eh heheh, anyone got one they'd care to lend me for a couple days??? :D

Guess I know what I'm saving up for now .. next toy :)

[littlesilvermax]

Interesting. Our LFS, SWC, has had good success with denitrators.

FWIW I have a BB tank and a good skimmer and 23 fish including 5 tangs, and I feed two tablespoons worth a day and can never even get detectible nitrate readings in it.

I do get about 10 ppm in my coral QT though.:sad:

[Delphinus]

10ppm isn't too bad. I don't know if it's my ritteri or if it's something else. On this 115g I also have my Calfo-recommended-DSB-in-a-bucket (which is a joke BTW, don't ever bother trying one of these). Both were in a 90g previously ("both" as in "the ritteri was in the 90g and the RDSB was run on the 90g) and that tank too, also had chronic nitrate problems. (And when I say "chronic nitrate problems" I mean "readings very consistently above 30ppm". I'm not sure how I managed to let this tank get to 75ppm, I really let things slide apparently :( ) Whether it's the ritteri that puts an incredible bioload on a system, or the RDSB is itself a source of nitrate due to something or other bound to the sand itself, I can't say .. both theories seem equally plausible to me at this point. I would have to check my tank logs because this goes back quite a few years now, but I think that there is a pattern of whatever tank I keep my ritteri in, tends to have higher nitrates than my other tanks. But this could be coincidence, it could also be due to the fact that these have always been secondary tanks and as such, not running as high-dollar-value equipment as the primary tanks usually get.

My next tank will be BB altogether. I'm happy to hear the positive results with BB, very encouraging.

[littlesilvermax]

BB is just soooooo much easier and cheaper and easier and cheaper and you get the point.:wink:

[Delphinus]

Yeah, I get the point. :D

I had wanted to have "one tank with a little bit of a sandbed" so I could keep things like my open-brain and plate coral properly (I feel these guys do better on sand). Although at the moment I guess it's a moot point. I lost my plate coral when I was in Hawaii because the Tunzes buried it in sand and my tank-sitter didn't notice and it never recovered, and the xanthid crabs totally went nuts on my brain one day and it too never recovered. Now I have a cube tank with a bunch of rocks, a 20" anemone, and a dozen crabs. I can't keep nothing but the anemone in there and it .. sucks. :( I would like for it to be a softey tank one day but I have to figure out how to de-crabbify the tank, I can't *beleive* how many of them came in. The thing that really gets me is that I inspected *each* rock closely before putting them in the tank.

Guess this is turning into a bit of an off-topic rant now.. oops.

Anyhow I'm curious about things like sulfur denitrators and Zeovit. For me, to try this was $25 in ARM sulfur beads versus $300ish to get started on Zeo. Seemed like a no-brainer but I would still like to consider Zeo or Ultralith one day, but maybe in a few months once I get a couple other things settled first.

[Delphinus]

Day 14

An interesting and potentially discouraging development. :(

Tank NO3 - still @ 75ppm (guessing, the colour pink does not match any on the chart, going on a guessed intensity)

Reactor effluent NO3 -- instantly off the chart. The colour readings only go up to 100ppm and you're supposed to wait a few minutes for the colour to develop, but the colour was well past the 100ppm right away when the drops of the second reagent were added.

I'm not sure what the next step is. Is this the reactor just cycling? Or is it a failure? :( I don't know how much faith to put into this thing to guess how long I should wait before taking it off.

Feeling mighty discouraged ... :(

If I could make up 120g of SW I'd just do a 100% water change at this point. I don't know what to do.

[Psyire]

Check your reactor effluent for Nitrite, if it's still cycling then you should have a reading I would think.

[Delphinus]

Good idea, thanks .. I'll have to see if I have a testkit that can tell me nitrite. I think I had one at one point but I think it might have been my Seachem testkit and I've finished that one a long time ago. :( Hate to buy ANOTHER test kit (have I ever mentioned I hate test kits?) but that may be what I have to do..

[Psyire]

I'm guessing your still cycling the reactor. Exactly 2 weeks would be about the time Nitrate spikes. (give or take 1/2 week)

I wouldn't do anything rash except maybe slow down the flow through the reactor if it's faster than a drip/second.

If you are still showing such high nitrate a week from now, then I would start to worry.

Double check to make sure your recirc. pump is running properly.

[danny zubot]

I might be coming into this a bit late Tony, but I have a pintpoint monitor that you can borrow if it will help.

I'm curious about something. This sulpher denitrater media, isn't it supposed to absorb NO3 kind of like a PO4 sponge? If so, why would there even be a cycle at all. I understand that it acts as a biological bed so technically there should be a cycle, but in removing NO3 from the equation shouldn't you eliminate the cycling process? Or, is it merily a substrate for concentrated colonies of anerobic bacteria to denitrify the water?

[Delphinus]

It's the latter case Danny, i.e., it's a substrate for anaerobic bacteria to take hold. I expected it would take some time for the bacteria to take hold, but I didn't expect that it would take hold with the nitrate-producing bacteria (which I thought was aerobic) first. The pH in the reactor went down within 2 days so I thought that meant it was an anoxic zone at that point, meaning from that point forward it would be the anaerobic bacteria colonizing the sulfur beads. I guess it's going to progress through various spikes but now I wonder if I should move the reactor off my tank and instead run it off a bucket of old water change water just to make sure I'm not dumping NO3 and NO2- into my tank unnecessarily (which I assume is not so good for the tank inhabitants!)

I'll send you a PM about the monitor. Thanks!

[andresont]

It's the latter case Danny, i.e., it's a substrate for anaerobic bacteria to take hold. I expected it would take some time for the bacteria to take hold, but I didn't expect that it would take hold with the nitrate-producing bacteria (which I thought was aerobic) first. The pH in the reactor went down within 2 days so I thought that meant it was an anoxic zone at that point, meaning from that point forward it would be the anaerobic bacteria colonizing the sulfur beads. I guess it's going to progress through various spikes but now I wonder if I should move the reactor off my tank and instead run it off a bucket of old water change water just to make sure I'm not dumping NO3 and NO2- into my tank unnecessarily (which I assume is not so good for the tank inhabitants!)

I'll send you a PM about the monitor. Thanks!
http://deltecaquariumsolutions.com/documents/TheNFPRangeofDenitrificationReactors_000.pdf

Deltec is indicating that you need 3 month to cycle the Denitrator!
Quote from manual.
"Note that the flow rates shown above maximum rates and are only achievable when the reactor has been fully
matured for over 3 months and is operated in full automatic mode with a water temperature of 20-30 C."

[Delphinus]

Wow 3 months. I was reading through the instructions for the Midwest Aquatic's version as my guide. If there's mention of a cycle time that long in there then I've overlooked it.

I guess it makes sense to take a long time for the right bacterias to colonize...

Wow though, that's a long time to wait .. Guess I'll stop posting my updates every few days that's just not gonna work out as an interesting thread.

"Day 300 reading ... everything is the same as before"

[andresont]

Wow 3 months. I was reading through the instructions for the Midwest Aquatic's version as my guide. If there's mention of a cycle time that long in there then I've overlooked it.

I guess it makes sense to take a long time for the right bacterias to colonize...

Wow though, that's a long time to wait .. Guess I'll stop posting my updates every few days that's just not gonna work out as an interesting thread.

"Day 300 reading ... everything is the same as before"
It has been very interesting, hope to see this project going.!
keep us up dated.
thx

[Psyire]

Midwest Aquatic's Sulphur comes with bacteria pre-installed. 'so to speak'

I should have my new unit soon, and I plan to just add some bacteria from my 'Polyplab Reef-resh' kit directly to my reactor in order to speed things up a bit.

[Psyire]

3 months does seem excessive though...

Would it take this long for DSB anerobic bacteria to establish themselves?

[Delphinus]

I imagine it might.

3 months .. I had no idea. I thought reeferaddict saw results sooner than that, so I'm still hoping there's hope.

Seriously if I have to wait 3 months to see an effect, I'd be better off doing a 100% water change and taking this thing offline. 75ppm is WAY too high to live with. Tank looks like crap too .. I dunno. Feeling a bit bummed out about this.. :(

I didn't realize the Midwest unit came with bacteria seeded media. I missed that. I should have used that stuff instead of the LSM then. :(

[reeferaddict]

My results took about a month to develop and have been very consistent since. Before I did the denitrator I battled hair algae and the sort for a year and a half. The tank now runs a tidy ZERO and that even with not getting to a water change in 6 weeks now.

The sulfur does need to colonize denitrifying bacteria in an anoxic environment. To do this I ran mine on a rubbermaid of 80 ppm tank water with a slow drip rate to begin with to promote the anoxic zone and gradually ramped it up to around the 5X media volume turnover per hour as stated in Delbeek and Sprung Vol 3 and waited to see my test water nitrates drop. I noticed a drop after about 3 weeks and after a month there was no nitrates left in the test water. During that time I had gotten the main system down to a reasonable 20 - 30 ppm. It took about 6 weeks on the main tank before my nitrates really dropped, but after 2 months there were ZERO which is where it's been ever since.

You need to keep an eye on the effluent rate, as I've had mine clog a couple of times and when you start up you get that wonderful rotten egg hydrogen sulfide stench, but even restarting it in the system doesn't release enough to be of concern to the inhabitants. I've seen nothing to compare to the nitrate elimination potential of this system. For the most part it's set and forget when implemented with a little research and common sense. Be patient - about all I can say is you may want to try increasing your effluent rate and see from there. I was dauted by mine at first - but it works beautifully! :mrgreen:

[Joe Reefer]

Reefkeeping rule #7234 - Nothing good happens fast. :mrgreen:

[danny zubot]

bacteria pre-installed.

**Insert Bacteria Here** :lol:

Tony, why dont you do a nice sized water change, and then run the unit out of a rubbermaid. Sounds like a good idea to me.

[Skimmerking]

Reefingkeeping rule #7234 - Nothing good happens fast. :mrgreen:
and more so when your married

[Reefer Rob]

Have you checked the calcium level out of the 2nd stage? In theory, with the sulfer producing acid, this may be a replacement for the CO2 bottle in a calcium reactor, or a least be of some value for calcium replenishment even if the goal isn't NO3 reduction.

[Delphinus]

Not yet. Randy Holmes-Farley did this article about sulfur denitrators where he showed the chemical reactions happening and demonstrated how the calcium and alkalinity, although there will be some, won't really be a significant source for the tank. However I'm sure it's still better than having nothing.


gradually ramped it up to around the 5X media volume turnover per hour as stated in Delbeek and Sprung Vol 3

How did you ramp it up? I'm still running about one drop per 2 to 3 seconds. Could I start opening it up at this point?

I don't have vol3 yet. I dropped a pretty big hint to Santa though.

So ...

5x media volume. I'm using a 4" reactor and my media height is approx. 8.5".

So roughly PI * 2^2 * 8.5 (Pi * r^2, where r=2 because diameter is 4") = ~107 cubic inches

1 cubic inch = 16.387064 millilitres

Therefore 107 * 16.387064 = approx. 1750ml

1750ml * 5 = 8750ml/hour

8750 / 60 = approx. 145 ml/min

That seems pretty fast to me. Am I overlooking anything or should it really be opened up that fast?

I guess that's only about 6 seconds to fill a 15ml measuring spoon. A little more than twice what I run my calcium reactors at (I run mine at 60ml/min) so I guess it's maybe not that far off. Hmmm ... interesting.

Ok so the real question is how much time do I give myself to open up the reactor to that speed?

[christyf5]

Arggh math! My eyes!!!!! :razz:

I say damn the torpedoes! Full speed ahead!

Seriously though, that seems pretty fast, why not just try a fast drip for now, then ramp it up from there?

[Psyire]

I don't think you want to be increasing your drip rate...

You want a slow drip rate until you have enough bacteria to use up all the nitrate at that rate. Then you start increasing your drip rate slowly until you find the right rate for your current bioload. As your nitrate in the tank comes down you will further increase your drip rate until it is balanced at Zero nitrate in the tank, and zero coming from the reactor.

[Psyire]

2 weeks is too early to be jumping to conclusions and changing operation of your setup..

[Delphinus]

Be nice now. I'm not jumping to conclusions but I am questioning whether I should wait to see this thing help sort out an immediate situation I have right now.

3 months from now is practically March and that's a long way's away. Many things can happen in that timeframe.

As far as increasing the drip rate, I haven't. It doesn't make sense to me to start that until I see a NO3 reading on the output that's less than the input, because until then, there obviously isn't enough colonization to make the difference.

[Psyire]

Sorry, I didn't mean that in a 'not-nice' way.

Personally I would give it another week to see if anything changes. You should show a lower nitrate level by then I would think. 3 months seems like an aweful long time.

[Delphinus]

Day 23

Pheh, this is getting a little past ridiculous now.

I don't have a very good nitrite test kit, but I do have nitrate/nitrite test strips, which do at least confirm presence of nitrate and/or nitrite and useful for observing trends but I've found the numbers corresponding to the colour chart to be innaccurate so I don't use the test kit for determining absolute values.

However it does confirm the presence of nitrite in the reactor, and has been showing this for almost a week since I started using it. No reduction in nitrite level, in fact, the colour for nitrite is off the chart.

I last tested nitrate of the reactor at day 18 and it was still off the chart (i.e., >100ppm nitrate). However I wonder if a nitrite reading would throw off this reading. I haven't been able to procure a proper nitrite test kit, if I have time to pop into Gold's on Friday I'm picking one up (all other LFS's I've tried are either sold out or don't carry Salifert nitrite kits). However I'm somewhat leery of spending $30 on a test kit that I'll never again use after this little sulfur experiment...

I expected two outcomes - the first and more optimistic was that this would prove to be viable for me. The second and less optimistic was that it would still work, but the small volume of media I'm using would prove to be ineffective on a 115g overall volume of tank. Frankly I didn't expect at all that it would seem to be incapable of growing the requisite bacterial colonies and be completely ineffectual as a result. I'm now wondering if there is something about how I've set it up, that is incorrect, or perhaps sub-optimal for running a sulfur reactor. I really wish I could see a working model in person .. I'm basically at a loss.

In the last week, I have run two 25% water changes (I don't really have the means to do a water change larger than 30 gals, I don't have a large enough reservoir to make more makeup SW) and that should put the tank nitrate level to approx. 40ppm from the initial 75ppm (75% of 75ppm =~ 56 ppm, 75% of 55ppm =~ 42 ppm), I've also moved my mangroves over and planted them in the remote-DSB, I've also made a chaeto cage and moved some chaeto onto this tank so I'm now throwing all I've got at this tank in an effort to get the nitrates down to a tolerable level .. there is a point of diminishing returns though and I don't mind admitting that I wish this sulfur reactor would kick in at some point. 3.5 weeks and no positive trend yet ... well we'll see where this goes. Maybe it's just me, and it's just not going to work. I'll give it a few more weeks but I guess there's no point in more updates at this point until there's actually a change to report on.

[andresont]

thank you for keeping this thread active !
I was just wondering:
How much media do you have in your chaimber?
how much flow is going through?
do you recerculate water inside the unit?
Thank you.

[Delphinus]

Hi,

The volume of media is around 1750ml (so just under 2 litres), which works out to about 1/3 (give or take) of a 1 gallon container of Caribsea LSM.

Flow rate is one drop per 2 to 3 seconds. I haven't worked out what that corresponds to in terms of ml per minute. I think I should work that out, I'll measure how long it takes to fill a 15ml measuring spoon tonight and post back here as that's probably good info to have to help determine whether something is set up right or not.

The water is being recirculated in the first chamber (the sulfur media only) by a mag2. The second chamber (ARM media only) is single pass.

One thought I had is that it's very difficult to determine how well the mag2 is pushing water through the media. I was wondering if it's possible that it's blocked and maybe that could explain things a little? Unfortunately I haven't worked out a way to figure out if there is flow through the media. If I blow bubbles into the intake, I could see where the bubbles go, but then I'm introducing air into the chamber and I would have assumed that's a no-no. But maybe the mag2 isn't enough, maybe it needs a stronger pump to push water through the media.

Also it's a downflow style reactor, I wonder if an upflow would be better.

[andresont]

"One thought I had is that it's very difficult to determine how well the mag2 is pushing water through the media."

The way i see it you doing everything right. lets waite and see.
Perhaps you could put a "T" with a vlave in the recirculation line to see how much you actually recirculating (instead of blowing air in the unit).When you open that valve you could get an idea of how much flow you get or at least you know that Mag pump is has good flow.
Other then that i thank you for keeping us informed.

[Delphinus]

Unfortunately I don't have a recirc line on this reactor.

Anyhow I did blow some air in. Had to open my valve and reset it afterwards. But it did show the pump is running.

Tomorrow is day 28 -- four weeks and counting. Nitrates still off the chart, nitrites still off the chart. I'm about ready to give up. I don't see any downward trend in the numbers. I don't see how reeferaddict could have such profound results in a month.

Should have gone zeovit when I had the chance. My poor tank. :(

I suggest to anyone reading this, don't bother with sulfur denitrators, unless you're willing to wait 15 years to see results. At least for me it's just like the Calfo DSB in a bucket idea. .. it just doesn't work.

[christyf5]

Sorry to hear Tony, I had such high hopes that this would be the solution :neutral:

[Delphinus]

Me too. Yeah, I dunno. I don't know what to do. Maybe the commercial units have bigger pumps, or have an upwards flow through the media. Maybe there's a threshold volume of media that's needed and I just don't have it. Who knows. If I could see a working and proven unit in action I could compare notes... Oh well.

[andresont]

http://www.marinedepot.com/md_viewItem.asp?idProduct=KL9115

http://www.korallin.de/frmst2.htm


I wonder what is so fifferent between this and what you are doing?

[AndyL]

Tony,

Ok, working off some reading I've done on this topic - not first hand (I prefer coil based denitrators myself). Sounds like your through-put is way too fast, crank it WAY down until you start seeing effluent output with 0 nitrite / 0 nitrate (or get stunk outta the house - that'd indicate way too slow). Once you get that 0/0 effluent then start bringing up the drip rate slowly.

Definitely check that mag pump you're using for recirc... Although that kicks your cycle back to day 1 again (introduction of too much o2 - supposed to be a low o2 environment), if it's not working up to snuff - the lack of recirc could be causing some problems.

since i'll never find the link again - good rc thread: http://reefcentral.com/forums/showthread.php?s=&threadid=752497

[Delphinus]

Oh yeah, one thing is, the effluent has never had any kind of sulfurous scent to it whatsoever. Isn't that odd? I think it has be indicating something's not right here.

Yeah, maybe 1 to 2 drops per second is too fast for the volume.

I'm firmly convinced that this is not working and not going to work given an indefinite amount of time -- something has to change on it first.

[Skimmerking]

Tony do you have a pic of the reactor I would like to look at it for a sec..

[Delphinus]

Santa brought me Vol3 T.R.A. Within 5 minutes of reading it I found about 4 things I'm doing wrong with this arrangement and that's only reading a few paragraphs of the sulfur section, by the time I'm done reading it all I could find out a few more things that aren't right with how I'm trying this.

Soooo .. I guess this calls for a "do-over". I'll elaborate on the mistakes of this setup later (stepping out for a while now).

[andresont]

Sulfur denitrator experiment still alive !

[andresont]

Tony do you have a pic of the reactor I would like to look at it for a sec..
http://www.canreef.com/vbulletin/showthread.php?t=28791

you can try first page of this tread for the pictures..

[Psyire]

I'm interested to hear what you think you've done wrong.

Not very encouraging results though... but perhaps there is a reason(s) that we'll find out soon.

I'm getting quite close to starting my own experiment, with any luck it will be late next week.

[seashells]

If you feel the nitrate readings are off then I would ask some other reefers to test your water. I had a salifert test kit and got off the wall readings. I compared it to a friends test kit and also the store where I bought it. I found after comparing I had to divide my readings by 2. So its possible your kit is inaccurate.

Doug

[Delphinus]

So, bearing in mind I haven't read the section in detail yet, only scanned it, these are the things that caught my eye:

- recommend upflow instead of downflow to avoid compaction
- recommend flow control valve on input not output to avoid pressurizing the unit
- recommend media volume 1% of total tank volume
- something about the reactor height to diameter ratio should be something like 5:1 (I'll have to read more about that one)

My main thinking here is that the flow-through is too high, and the recirc is not enough. I don't know about switching to 1% tank volume as that will need a different reactor, same with changing the height/diameter ratio (actually mine may already be close to that anyhow, give or take). The main thing I'm thinking is switching the flow control valve to the input, leaving the output wide open; changing the flow direction to upflow; potentially scrapping the feed pump (since need to slooooowwww it down even more), and upping the recirc pump from a mag2 to a mag7 or mag9.

[Psyire]

Your last 2 points revolve around a 1-pass reactor if I'm not mistaken. I don't believe T.R.A. Vol.3 discusses recirculating reactors. (therefore volumes and flow rates are changed)

I wouldn't increase the flowthrough rate of the recirc. chamber if I were you. This will nullify the 'O2-Free' zone if the flow is too much.

You may want to check your test kits as stated above, just in case something is off. I would just run a nitrate test on your new makeup water, during your next water change to see what it reads.

[Psyire]

If changing your flow through the sulphur chamber I would actually go the other way and lower it. This will create a bigger O2-Free zone and therefore more anerobic bacteria. If your flow is too high I would suspect that you would get into the middle of the denitrification cycle and not have enough anerobic bacteria to finish the cycle off. (which would seem to be what your test results are showing)

[Delphinus]

No indeed, I want to slow down the flow-through. Sorry if that wasn't clear. That's what I think that's my problem right now, in that there's too much flow-through, even at 1 drop per 2 to 3 seconds, it's too fast. There has been NO sulfurous scent and everything I've read said that a too-slow flowrate will have a scent, and a too-fast flowrate will likely still output nitrates and nitrite. A bigger unit would probably help but that's not what I have to work with so I have to find another means of controlling the flow through this and slow it down considerably.

What I do want to increase though is the power of the pump doing the recirculation inside the reactor. It won't work to increase contact time but I think there's not enough contact with the media in the current arrangement with the mag2.

I've been using three different test kits to take nitrate readings, unfortunately they all agree with each other. Although I only have a test-strip for nitrite, not a full-blown test kit for that, and no secondary testkit with which to compare results. Nitrite's not really a commonly stocked testkit it would seem (I'd never consider buying one if it wasn't for this).

[Psyire]

Ah.

Well in that case I can't see how your proposed changes could hurt anything. Might want to do one at a time, starting with the cheapest being to slow the flow down 'through' the reactor. Then if that dosen't seem to help, increase the recirculation. That way you don't go the wrong direction twice by accident.

[Pansy-Paws]

My sulphur denitrator (sized at 0.8% of volume) dropped 40 ppm to zero in 4 weeks, after one week to cycle the denitrator. It does sound like your flow rate is in the right ballpark, so the O2-free zone must be getting disturbed in some way and not forming. Maybe upflow is the secret, as any nitrogen bubbles would rise back through the O2-free zone in a downflow design :question:

I wouldn't worry about the volume of sulphur. If it's too small, nitrate reduction in your system will simply be slower, and as long as it is sized large enough to counter the new nitrate production, you'll reach zero. Once it's cycled, you'll be able to tell if it's large enough.

I started out with two Phosban 150 reactors (one with sulphur, one with aragonite) to test the concept on my 500 gallon system, well short of 1% volume. With the effluent nitrates at zero for this test system, I knew that a larger design was required.

Myself, I've been having trouble with low pH for the effluent, so am looking to build a recirculation chamber with aragonite on the outflow to counter the problem.

Keep persevering ...

[Psyire]

Incase you are interested my reactor is going to be an upflow with a eheim 1250 recirculating pump.

I really have a hard time believing a Mag 2 wouldn't be enough for your application. The midwest units use a eheim 1048 which is probably 1/2 the flow of the Mag 2, and their unit is quite big.

[Delphinus]

One week to cycle ?!

Man ... I feel so ripped off.

Anyhow, I've taken mine offline for now. Will tinker around tomorrow or the next day time permitting .. I agree about the sulfur amounts -- seems to me if it's too small it should just not be able to pull down the tank nitrates as quickly -- but should still cycle and still output zero. At the very least I'm going to swap the pump leads to reverse the flow, and if the recirc pump isn't enough to draw sump water then I'm going to fashion some kind of gravity feed and see how ridiculously slow I can make the flowthrough.

Don't know what to say about the Midwest units using a smaller pump. All I can say is I gave it a month .. and it wasn't cycled so I know something's not right. All I can do is guess at what ... I wish I had more answers.

[reeferaddict]

:mrgreen: Mine is still keeping everything at zero.... :biggrin:

[Delphinus]

I'm so happy for you. And thanks for the plentiful and bountiful suggestions on getting mine to work! You rock! :p

[reeferaddict]

Why Tony - I have a whole thread on the matter! In your defense, it seems to be a 50/50 split as to whose works and whose doesn't.

I have about 2 litres of media for close to 200g of system volume with about a 8 - 10 litre per hour of output. A few times mine has clogged as the aragonite dissolves and I have to open up the valve to "flush" the effluent, and I end up with the wonderful rotten egg smell, but other than that it has been pretty much set and forget except for the initial cycling which I wrote about in my thread. One water change of about 10% per month and still zero nitrates - I was pulling my hair out and going through a hundred bucks a month in salt before this little beauty.

In retrospect, considering the time I have been limited to with my system in the past few months, it would be just a green wavy sea of algae by now without this wonderful little gadget! :mrgreen:

[Delphinus]

Why Tony - I have a whole thread on the matter! In your defense, it seems to be a 50/50 split as to whose works and whose doesn't.

I know you do, but in all fairness there isn't a lot of info in there for people who want to duplicate a reactor. If I found a Koralin 1502 or whatever then there's maybe enough info. As for nitty-gritty details like whether it's upflow or downflow, pressurized or not, detailed time-based data on the #'s as the unit cycled, and so on .... you neglected to mention those! :p So sorry for razzing you but seriously, you were dancing on my misery so I had to give you a hard time about it.



In retrospect, considering the time I have been limited to with my system in the past few months, it would be just a green wavy sea of algae by now without this wonderful little gadget! :mrgreen:Would love to be able to duplicate those kinds of results .... well we'll see what trial #2 brings. It's not as easy as "just put some sulfur in it and turn it on and then angels will sing songs in praise of your reef" otherwise I wouldn't be still scratching my head on this one. ;)

[Delphinus]

Ok was able to tinker around a bit and got the plumbing switched around so the reactor is now an upflow. And I see the mag2 will be more than enough pump because it completely fluidized the entire media column. Before I continue I'm going to have to go get a round sponge (fluval etc.) to make sure the pump intake doesn't suck in media.

And I switched the feed to use my dripline off my overflow. I normally use this to drip in new arrivals. I put an irrigation dripline needle valve and was able to dial down the feed to 1 drop per 10 seconds and I have room to slow it down more.

So .. tomorrow I'll hopefully be able to finish off the upflow mods and get this going again. I've just gone from bummed to stoked! Hopefully there will be some learnings we can share from all of this in the end. :)

[AndyL]

Not loving that feed, simple reason - if you cut power etc - you risk introducing air... These reactors work in an anoxic (low oxygen) or anaerobic environment, introduction of air (due to say return pump failure / turning it off for maintenance) would harm the bacterial culture.

Low tech fix - mechanical float - similar to RO / top off floats... So if water level drops below a set height it cuts off flow.

Lower tech fix - add another valve as a cutoff for maintenance (if your like me - add a reminder label to the plug / switch for the pump) and prayers go a long way I'm told :)

[Delphinus]

There's already a shutoff valve, so the pump maintenance angle is covered.

In the case of a power failure .. there may be some air introduced .. I'm not sure how to completely eliminate that variable. I had also thought of using a separate feed line from one of the overflow chambers but it's basically still the same problem, in a power failure it will siphon until it sucks air.

There are a couple mitigating factors though, which I thought might have been enough: (I dunno, maybe not? I realize it's not foolproof but this is why I decided to chance it...)
- the reactor sits lower than the sump wall, so the reactor itself doesn't drain. There's always water in the 2 chambers.
- With an upflow and the output of the 1st chamber fully open, and on top, any air will escape out right away. It might make 1 pass through the media but hopefully no more.
- They say when the reactor's cycled, that you can increase the flow-through, so obviously the media can handle some O2, just not a lot. (??)

Anyhow, this is the only way I can see to slow down the flowthrough considerably from what I had before. Since you can increase the flowthrough once it's cycled I was hoping to change the feed once again to something else (after all I want my drip acclimation feedline back sooner or later).

But if it's no good then it's no good.

I'll try seeing if the recirc pump is enough to draw water from the sump, before going online. If that will work then it's not too hard to ensure that the input is always submerged. Thing is there are a lot of bubbles in the sump so the odds of sucking in the stray air bubble are also nonzero in this situation either. Although probably less and also don't have to worry about the power failure scenario.

[reeferaddict]

Tony - when I got mine I had no info besides what is available online and in Delbeek & Sprung Vol 3. I wasn't really wallowing in your misery, rather encouraging you to keep with it.

I don't care what your vessel size or media volume is, this "system" will work.

On my unit I use a MJ pump to feed the intake which is where the flow control is to avoid the pressurization of the container. The intake goes down into the bottom of the vessel as with a kalkreactor. An Eheim 1048 is the pump used to recirculate, and when I cycled it I set the effluent at 1 drop per second, increasing it when the NITRITE levels disappeared. I gradually amped it up to around 5 litres per hour which is where I had intended running it on my system according to my research. Once cycled at that rate, (EG. - the water used to cycle it results in being nitrate free), I stuck it in my main system which was at 20 - 30 ppm nitrates from massive water changes. It took 2 months or so to see it get to zero, but I didn't do any water changes until it got down to zero. During this time was when I discovered it not circulating a couple of times, but all I did was open up the valve all the way to flush out the gunk and it seems to have had no effect. I think once the sulfur is colonized it would actually take a severe flushing with highly oxygenated water to actually kill it. Even after a couple of lengthy power outages this winter it seems to be fine.

I don't know what else to tell you to help here. Mine is a Korralin 1502, but that doesn't make it a set science here. It's the principle of the concept and patience. I believe the only way to have sped up my process would have been to increase the sulfur volume, but everything else would have remained the same.

[BCOrchidGuy]

Tony, I've just got to say it's a damn shame that it's not working for you yet but I think you deserve a pat on the back for trying it, I'm sure you'll get it soon now. Good luck and all that jazz.

Doug

[Delphinus]

Thanks Doug. I hope it can be made to work, I used water changes to get the 80ppm down to about 40ppm, but now I'm at the point of diminished returns -- the same # of water changes would only get me down to 20, and the same # after that would only get me down to 10. When all is said and done and .. that would be a lot of salt. :( So I'd love to see this concept work.

Are all sulfur media's created equal? I figured, sulfur is sulfur, right?

Riddle me this - I have yet to encounter even the slightest hint of a rotten egg smell. Even yesterday, as I drained the unit to work on it (switch from downflow to upflow), it had been sitting idle for 24 hours, .. the water coming out smelled fresh. Not a hint of sulfur scent.

Would this be expected?

Reeferaddict, are you using Caribsea LSM or did you go to a winemaking store and get something from them?

[Delphinus]

Ok new update. I was out of town last week and got back Monday so on Tuesday (Jan. 2) I was able to finish off the mods for upflow and get the reactor going again on my test tank.

So after a couple of days, there's been a bit of an "interesting development" as well as a "slight disappointment."

The bad news for me is that the nitrate monitor I ordered came yesterday and it appears to be defective. I can't get a reading out of it despite many calibrations, and the readings I get on the calibration fluids, after calibrating, are whacked out. (For example, 93ppm on the 10ppm calibration fluid). Bummer.

But, I did some old-school tests and came up with these readings:

NO3 of tank water - 50ppm
NO2 of reactor effluent - 0
NO3 of reactor effluent - 25ppm

I'm somewhat suspicious of the #'s since they're indicative of a nearly complete cycle at 2 days already, so it will be interesting to see what the numbers are at in another 2 days. I was expecting the nitrite #'s to be non-zero for a while yet, if it went non-zero and came down then I've missed it already. Since they hadn't come down after 4 weeks on the previous trial I'm at a loss to explain the profound difference.

I should mention that besides changing the unit to a non-pressurized upflow design, I also have the flow-through cranked way, way back. Unfortunately due to the flow control being on the input, getting a consistent flowrate day after day is a bit of a challenge, but the last time I measured the flowrate it was approximate 3ml/min. That's 180ml/hour, or assuming a total water volume of 115gal, about a 0.04% volume turnover per hour, or just under a 1% volume turnover per day.

[BCOrchidGuy]

Tony, Not sure how the numbers work out but have you considered using garden irrigation drippers? I used a 1/2 gallon per hour dripper on my old Ca reactor, yes it clogs up after a couple of months but changing them is easy and they are affordable.

Doug

[Delphinus]

That's a cool idea! I can see that working well for a Ca reactor. Unfortunately that flowrate is far too fast for cycling this thing, since what we need is an oxygen-free zone to kickstart the anaerobic bacteria, so have to really restrict the amount of oxygen being introduced. I almost wonder if it's better to close the input altogether and open it slightly only once per day just to get the cycle going. Once the bacteria is settled I should be able to open up the flowrate, after all 1% volume turnover per day is not going to touch the tank's nitrates in any scenario.

[Psyire]

Glad to see some encouraging results!

[andresont]

Two days and 25ppm NO3! what a difference pressure can make. May be you already had bacteria there, and when Bacterial headache is gone they just got hungry !

[Delphinus]

Still being somewhat suspicious of the #'s I tried testing again tonight using a different test kit. The first were done with Salifert, so tonight I tried with Elos.

I suspect that the Elos kits strengths are in the lower ranges. I took two test tubes side by side and did the input and output water together. I had to stare at the colours for a long time before deciding that one did indeed seem "less pink" than the other. The only sorta downer is that the pink matches more like 75ppm and 50ppm. :neutral: I think I must be colourblind because I really have a heck of a time staring at pinks and trying to compare to the colour chart. They're all "fuscia" to me. :neutral:

I talked to American Marine earlier today and I'm told that I'm the first one to call about any problems with their nitrate monitor. (Yay me! Go team!! Wooty!! :( ). Anyhow he gave me some suggestions but there really isn't a lot to work with (short of leaving the probe in the calibration solutions longer). The readings, if not clamped at over-range, are hugely fluctuating. For example tonight I got it to read anywhere from 30ppm to 100ppm to over-range on the 100ppm sample. I'm going to talk to them again tomorrow or Monday, hopefully we can get it working right or determine that it can at least be replaced if nothing else. I'd love to see what the readings are with something that can tell me real #'s as opposed to "in the neighbourhood of 50 to 75ppm".

[Delphinus]

Well ... I'm at a loss again.

At the end of day 7 I tested NO3 on the tank and the reactor output, using Salifert.

Tank - 25ppm
Reactor - 25ppm

I'm completely puzzled by this. Did the reactor start outputting at 25ppm earlier like I thought it might have been, and it's pulled the tank down to 25ppm in the days following even though the feed is super-duper slow?

Or is it more likely that the chaeto in the tank, which has suddenly kick started a growth spurt, has sucked up some nitrate?

So .. tonight (day 9) I test the reactor effluent with my Elos test kit.

You're supposed to add the reagents, then shake for 5 minutes to wait for the colour to settle. Well within 30 seconds the colour was darker than the darkest colour on the colour chart (much like before on trial #1), which in the Elos NO3 testkit is 75ppm. So the reactor is outputting >75ppm again? Huh? What gives? Does the Elos test kit colour actually fade in the 5 minutes unlike other test kits where it gets darker the longer you wait? Or am I messing up the testing? Or is the reactor outputting a super high nitrate for real and my Salifert test kit is out of whack?

I'm completely at a loss to theorize what's going on here.

The one tool I had hoped would help clarify things, the nitrate monitor I bought on Boxing Day, is seemingly defective, and has been sent to American Marine directly to troubleshoot and repair or replace if need be. In the meantime I'm out the $300 and I'm out the unit until it gets sent back to me. (I trust the issue will get resolved satisfactorily .. I'm not knocking the service I've gotten, I'm just disappointed I can't use the unit as a yardstick for my nitrate levels because trying to make heads and tails of these test results ... simply sucks!) :lol:

Gonna try rearranging my reactor feed situation and see what I can come up with. I'm determined to see successful results dadnamitall!!

[andresont]

If i could only have as much patience, determination and drive as you do!
There are like gazillion people watching this...
How about we do a mass consciences experiment and visualize the following:
All test kits are accurate
Denitrator is working properly
And nitrate monitor comes back very soon in perfect working condition !

[Psyire]

On day 9, what did the salifert test kit show? Still 25?

[Delphinus]

Didn't get a chance to test with the other test kit, by the time I got around to the testing I had only a few minutes before the tank lights turned off, and the (as yet undeveloped) basement is too dark at night without the tanks on. You're absolutely correct though in that I need to do both testkits at once and do a side-by-side comparison to try to makes heads or tails of this.

What's weird though is that my nitrate/nitrite litmus test strips that I was using previously to tell if there was nitrite or not, are not registering any nitrate or nitrite, three tests in a row now where a strip has been dipped and there's been no colour change on it. It is an old set of test strips though, so more than likely the explanation for this one is they finally hit their expiration and I should just toss the rest.

I should be doing the testing at high noon and comparing the test tube colours outside in full sun. I bet then I'll get some lower #'s! ;)

[Delphinus]

Okey dokey. End of day 10, got a chance to go a little test crazy:

Tank water:
Salifert NO3: could be 25 or could be 50
Elos NO3: darker than 50 but lighter than 75
pH: 8.2

I'm going to split the difference and call it "50ppm NO3" in the tank.

Reactor effluent:
Salifert NO3: 50ppm
Elos NO3: >75ppm (chart only goes to 75, it was darker than the 75 reference)
Salifert NO3: >= 4ppm (chart goes to 4.0, was at least as dark as the 4.0 reference, I think it was pretty close actually)
pH: 7.6

Soooo ... my interpretation: The Elos nitrate test kit is thrown off by any presence of nitrite in the test water. Reactor is definitely not cycled at this point.

I'm not sure if this is a good idea, but I shut off the feed altogether tonight and am just letting the water cycle through the sulfur with the recirc pump. If the problem is too much O2 in the feed water preventing a cycle from forming then this should help with that.

I still do wonder if the LSM media is somehow not as good as maybe some other choice. The Midwest Aquatic media that comes with bacteria preseeded, for example, or maybe winemaking sulfur is somehow a more pure grade, or something like that.

[Delphinus]

Sorry that this is such a long thread.

Day 14:

NO3 - 75ppm (Salifert, not going to bother with Elos until the NO2 is gone)
NO2 - 2.0 ppm (!! :) )

I have the flow cranked way, way back. Like 1 drop per 5 to 10 seconds.

I really do hope I'm seeing a reduction in nitrite and not just wishful thinking. Will test again in a couple of days. I figure at this point there's no benefit to testing every day, but maybe 2x or 3x a week until I see the NO3 drop.

[Psyire]

Glad to hear some good news. The other day I stumbled upon someone saying that it can take 6-7 weeks for an unseeded reactor to establish the bacteria in some cases. (depending on conditions and nitrate levels in main tank) Can't remember where I read this though...

[Delphinus]

Day 21

NO2 still >2.0ppm. Didn't bother testing NO3.

This makes watching paint dry seem exciting. I know I need to be patient but the lack of a visible trend in the #'s really does concern me. Is nitrite reducing bacteria really that hard to get to colonize?

I wonder if I have bad expectations. Is it possible the sulfur won't colonize nitrite reducing bacteria? I.e., should I just increase the flowrate now? Flush out the nitrites and let the remaining bacteria (hopefully there is some by now) just reduce the incoming nitrate?

This is far too complicated. :( All I end up with is questions and more questions and no real grasp of what you're supposed to be doing.

[Delphinus]

I still wonder about the Caribsea LSM. I've read a few times where people say if their reactor clogged, that getting it going again you get a wicked rotten eggs smell in the whole house. I mean, I have to basically get my nose right into a sample of this water, sniff it as hard as I can, and if I use my imagination I might imagine a slightly sulfurous scent (ie., not even close to Banff Hot Springs kind of scent). Low grade sulfur maybe???

Apparently American Marine did find my NO3 monitor to be defective, it's on its way back to me. Hopefully it arrives soon and I can start using it to track nitrates instead of guessing-the-pinks.

I might as well try a coil denitrator at this point too, what the heck, eh? :lol:

[andresont]

Can you combine coil denitrator with sulphur instead of bioballs?
I guess you wouldn't at this time eh?

I might as well try a coil denitrator at this point too, what the heck, eh? :lol:[/QUOTE]

[Psyire]

Have things changed at all?

I just recieved my reactor today, so I'll be starting it up shortly. Should be an interesting experience...

[Delphinus]

Just tested nitrite tonight and it was off the chart again. Guess increasing the flowrate was the wrong thing to do. :neutral:

Cranked it back to 1 drop per 7 seconds.

I have to wonder that something's wrong with this scenario. There must be too much O2 coming into the unit preventing a proper anaerobic zone. Next time I'm at Home Depot I'm going to buy maybe 50' of 1/4" tubing to add to the inlet. Not sure what's left to try after that.

[Delphinus]

Someone at RC has suggested to me maybe the problem is that the sulfur interferes with the test kits.

If that's the case, it could explain a LOT.

However if that's the case then I don't know how to tell if the unit is working, or when it's time to increase the flowrate.

Hopefully my nitrate monitor arrives back soon. American Marine did confirm it was faulty, and repaired it and sent it back. The only thing is it took almost a full two weeks to get to them (and this was the "U.S. Parcel Expedited" service from Canada Post), and so I would expect it will take at least as long to return. Been about a week and a half since they sent it back so with some luck it does come this week. At least I feel a little vindicated on that one, he had told me that of the hundreds they've sold I was the only one to complain it wasn't working, then when he looked at it he confirmed it had a wiring fault. Anyhow at least it's been fixed but it would be nice to have the thing back soon!!!

[andresont]

I was just thinking ... would it be possible that your recirculation pump sucking in micro air bubbles? That would change a lot of things what do you think? Can this be the unnotocied problem?

[Delphinus]

Ask, (or maybe in my case, whine) enough and ye shall receive. :)

Yesterday the nitrate monitor arrived in the mail! "Woot!" :lol:

It looks like it's immune to the sulfur interference. I tested the tank and it read 26ppm and I measured the reactor effluent and it read 13ppm.

So maybe this thing has been working all along... I guess the lesson is learned, you need to take a leap of faith (or find a test kit that's immune to sulfur interference, and FWIW that's neither Salifert or Elos).

[Farrmanchu]

There you go! Now you can get the reactor dialed in right. 13 ppm is allright, betcha it takes a few weeks to get the output down to 0ppm. It WORKS!:wink:

[Delphinus]

One week later and the effluent still reads 13ppm so I'm going to try slowing it down somewhat in an effort to get it to read zero (so that I can increase the flowrate and have it attack the "ambient tank nitrate level").

In the space of one week though my tank has tested as low as 21ppm NO3 (which I thought was pretty good) and as high as 31ppm. In fact, it tested 21ppm 3 days ago and yesterday it tested at 31ppm, so a full ten point increase in two days.

I'm at a complete loss to comprehend such a jump in nitrates. I haven't fed my anemone at all in a couple weeks, and I've been lightly feeding the one fish in there (a juvenile S. virgatus rabbitfish). His tankmates are 2 cleaner shrimp and 2 peppermints, plus some snails and 2 urchins. This is a 110g tank so I would consider this to be on the low end as far as bioload is concerned. The big question mark is the anemone ... near as I figure it is some kind of weird nitrate producing beast but I would have thought that output would correspond to input but it seems as if it doesn't matter if I feed it lightly or feed it heavily, the nitrate is always there.

I am starting to think that the tank needs a major overhaul.. maybe a larger sump so I can increase the rock volume, and maybe a skimmer overhaul or upgrade. I guess there's the possibility of testing errors on my part but it seems suspicious that I'd get a reasonably steady level on one thing and at the same time such a wild fluctuation on the other.

I think this is just a weird tank to be trying this experiment on. Something is just not typical/average here.

[Delphinus]

Today = February 13
Started = January 2
-> So exactly six weeks

Today's readings:
Tank = 30ppm (up from 23 two days ago again, it crept down over the course of the week until now)
Effluent = 23ppm, 2 drops per second

At what point does one accept that something is just not going to work? I don't know where to go from here. It's bad enough to see a lack of tank nitrate reduction but to see such huge inexplicable jumps is insult to injury. I haven't fed my anemone in weeks, the only thing I can think of is that I fed my ONE fish some NLS pellets and an extra pinch for the shrimp, but to see a 10 ppm increase overnight in a 115g? That has a skimmer and a denitrator AND a remote-DSB AND a chaeto growout AND some mangroves? Doesn't make sense to me.

[Psyire]

Compared to my setup I think that the Mag 2 is possibly too big for your application. A slower flow through your sulphur bed would create a more ideal environment for the anerobic bacteria. I'm running an eheim 1250 (a tad smaller than a Mag 2 for flow) on a much bigger reactor and it seems to be running great. Other than that, the only real difference between our setups is that I seeded mine with bacteria. (even though the CaribSea LSM is suppose to have some bacteria already seeded into it)

[Delphinus]

Update - I'm taking mine offline as soon as I have some time to get on my hands and knees to undo the plumbing and clean out the reactors and recover whatever media. In the meantime it's not hurting anything so I'm leaving it there but it's definitely no-good.

About two weeks ago I finally gave up hope altogether this would ever work out for me, so I decided I'd take it offline at the earliest opportunity (but left it on in the meantime since it wasn't hurting anything ... not doing any good, but not doing any harm, so I figured it could wait until I was looking for something to do).

Anyhow I stopped testing my effluent on Feb. 20. Sometime between then and yesterday the input line vapour locked and the siphon stopped so there was no flow. When I discovered this I did a nitrate test of the water in the reactor, and lo and behold I got (for the first time since NOVEMBER) a zero nitrate reading on the water inside the reactor.

So, I thought I'd give it one last kick at the can. Restarted the siphon and reset the drip rate to one drop per second.

24 hours later (tonight), the effluent is back up to 20ppm. (Tank is 35ppm.)

So ... I guess that's it. I'm done with this for now. My guess is that there's just not enough media, despite what people keep telling me that "its enough media" I think the numbers just tell a different story.

Psyire, how much media do you have in yours? Can you do a volume calculation? Even just a rough guess, like "1/2 container of LSM" or "3/4 container" or "2 containers" or whatever is fine. I'm just curious to see how it compares - you said your reactor was much bigger than this reactor so I'm curious as to how much bigger it really is.

[Psyire]

Sorry to hear....


But to answer your question.. 1.5 gallons (containers) of LSM. With a recirculation flow rate slighly lower than yours with the Mag 2. (this is where I believe your problem lies, but that's just my opinion) If you lowered your recirculation flow I think you would get closer to where you want to be. With a high recirculation flow I think you are getting oxygen present through your entire reactor. This is somewhat proven by your zero nitrate reading once your input was cut off.

I would be tempted to swap out that Mag 2 for a ehiem 1048 or something similar. Trust me, the results of lower nitrate are quite nice, as I have corals growing again that had stops for many months. It's made me a believer... so far.

[Delphinus]

You're probably right in that I should try a smaller pump, but I figure if I'm going to have to spend money to buy a pump I might as well also try a bigger reaction chamber because the small volume of media is really a wildcard I don't trust anymore. I could try swapping out this reactor for my calcium reactor and make this one a calcium reactor again or I could try to build something. I suppose I could try to find an Eheim 1048 or I wonder if I should just put a 1/2" ball valve on the output of the mag2 and set it to 1/2 or 3/4 to slow down the flow.

Oh well .. I went into this wondering if I could convert "this calcium reactor" into a functional denitrator, .. now I know the answer is "no - not this calcium reactor anyhow (but not to say one couldn't use another one)."

The next thing I want to work on is upgrading my G3 into a meshwheel and reworking the sump. I think it will be an interesting project. Maybe after that I'll look into trying the sulfur again, but for now I'm shelving the idea.

[Psyire]

I wonder if I should just put a 1/2" ball valve on the output of the mag2 and set it to 1/2 or 3/4 to slow down the flow.

Why not do this before shutting the reactor down? It's a simple thing that may work perfectly... (and cheaply)

[Pansy-Paws]

Have you tried shutting the recirculation down for a few weeks to see if the media will seed more completely? I don't have recirculation myself, just a single pass through of the LSM (0.6% of the tank volume ... about 3 gallons), so I'm somewhat suspect of that component of the design simply because I've not used it myself. I do, however, have recirculation on the aragonite media to get the pH back up before re-entry into the tank ...

I've shut my unit down several times in the past six months, and during start up the key to reseeding is ultra ultra slow flow, and leave it there until you have a slight smell of sulphur (with your nose right at the outflow), then crack the flow up a bit (wait a few days for the slight sulphur smell to return), and repeat ...

The amount of sulphur relative to tank volume won't affect the zero nitrate formation (after all, the bacteria don't know how big your tank is), but with less volume you definately need slower flow, which can be a major obstacle. If I was to speculate without seeing your system, I'd say the flow is likely the factor that isn't correct yet and as a result, complete seeding of the media has not occurred. As well, if the length of the denitrator isn't at least five times the diameter of the cylinder, the drip rate would need to be even slower than usual to compensate and create the anoxic zone. I use a gate valve for flow control, but those can get spendy.

That zero reading you had would indicate that a super slow flow rate would give you success. For readings, I've found that the Jungle test strips aren't affected by the sulphur. Of course, you need to extrapolate between colours rather than simply reading from a digital device :biggrin: :biggrin:

I still swear by these devices for FOWLR systems with high bio load and heavy feeding.

[Delphinus]

New update ... This has taken a bit of a backseat since March but I got it going again recently.

I've reworked the sump baffles, I've modded the skimmer to meshwheel, and now I use a 100micron filter sock on the sump intake. I'm now happy with the tank and removed what I hope were stumbling blocks in its ability to process bioload.

I took offline my other calcium reactor from the other tank, and replaced it with the smaller unit (left it as upflow). Using the larger reactor now, I modded it to upflow (switching the tubes at the bottom, using a T at the top of the chamber for the intake, cut some eggcrate and got a filter at the top).

It's -just- large enough to hold an entire container of LSM media now.

The recirc pump is a mag5, the feed pump is a lift pump (looks like an airpump but for water) that pushes water, and flow control via an irrigation dripline needlevalve.

Using a 5g bucket of outgoing water change water, which tested at 21ppm NO3, I cycled the reactor (@1 drop per second) on the bucket and the results look like this:

(Date/Effluent Nitrate ppm)
2007/04/29: Not tested (source water = 21ppm)
2007/05/02: 15
2007/05/03: 10
2007/05/04: 7
2007/05/05: 0 (source water now = 4ppm)
2007/05/06: 0 (source water now = 0ppm)

So ... quite an astonishing change from the previous trials. Of course this is on a small volume of water with a static nitrate condition (ie. not being produced), but still, a reduction of 21ppm to 0ppm in 7 days to me seems pretty keen.

I'm more convinced than ever before that the problem in the previous attempts was inadequate media volume.

Incidentally the lift pump seems to be the answer to producing a nice slow flowrate. It has been rock steady at 1 drop per second all week and what tickles me most is that it's a $10 item. :)

I moved the reactor over to my 110g tank tonight, which tested at 33ppm NO3 (there is a good chance of error on this reading as I did it with the unit uncalibrated on the high range reading, but it is definitely in the ballpark).

It will be interesting to see how it does now that it's moved over into "production mode."

[Psyire]

Awesome News/Results

Glad to see you are giving it another go, hopefully with much better results this time around. I haven't posted any updates to my situation, but things are still ticking along just fine with my reactor and my tank has never looked better. (and tested better)

[Delphinus]

Murphy's Law had to kick in sooner or later.

This week's run started off promising, but has ended not so good.

Date/Reactor Effluent/Tank nitrate readings:
May 7: 10 / 33
May 8: 1 / 31
May 9: 0 / 31
May 10: 14 / 34
May 11: 21 / 32

Not sure what happened on the May 9/10 there, but ever since then Murphy's Law has been showing up. Haven't been able to keep a consistent drip rate since then either, so last night I switch the feed pump / flow control valve around so that the pump is Aqualifter pushing into the reactor (as before) but with the dripline irrigation valve on the output.

Worked awesome to get a nice steady rate, but, it looks like the reactor just can't handle the pressure. Although I have my flange bolts as tight as I can make them, water just seeps through the flanges like crazy. I wish I had noticed this last night (or this morning). I came home from my bike ride today (I left before the tank lights turned on), checked on the tanks and found a good 5-10gallons on the floor. Argh. :( And, I found that the intake tube had wiggled its way out of the sump and the reactor was just full of air bubbles. I figured at this point the bacterial cultures are a total writeoff and I have to start the cycle from the start all over again.

Bummer. For an inanimate object, it sure seems as if it's quite determined not to work. I tell you, between the nuisance crabs (who just killed a fish on me :cry: .. I have to declare an all out war on the little bastards now), the out of control nitrates and the out of control phosphates, and faulty test meters, my patience for this hobby is wearing dangerously thin.

Oh well, next week's another week, we'll see where it goes...