Sulfur denitrator experiment

[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 !