Sulfur denitrator experiment

[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

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]

Mine is still keeping everything at zero....

[Delphinus]

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

[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!

[Delphinus]

Originally Posted by 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 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! 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!

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.