Denitrifying coil works like a charm

[iliriano]

NO, I am not going to sell the things. It is basically a coil to remove the oxygen and after that you can run the water through bioballs or rocks, anything that bacteria will grow on. It also has to be sealed so the water does not get oxygenated inside. I used PVC pipes, one inside the other only because I had them.
I did not invent denitrification coils and there are many variations.
Just get about 40" of tubing, wrap it around a pipe or put it in a bucket and fill the space with bio balls or anything else that is inert. Put the top on and pump the water first through the coil then let it slowly go through the media, then back to the tank. In a month or two it should start to process nitrates but be careful. These things could produce hydrogen sulfide which is poisonous to sea creatures. I smell the effluent a couple of times a day because the stuff smells bad of rotten eggs.

ok, so what size pvc(D), total length of pvc, i would like to make one or if you could give a fellow reefer a hand being that you made it work. thks

 

[Paul B]

I used 40' of 1/4" PVC tubing. I think Home Depot sells it.

 

[c griseum]

I just recently built my first prototype just a little different than yours, Paul.
Im using about 90 feet of 1/4" tubing as a coil which then leads to a chambe similar to a 3 liter soda bottle full of media for the anaerobic bacteria to grow on. Ive been cycling it for about 3 weeks and its only now slightly lowering nitrate levels but its still spewing out VERY HIGH nitrite readings, like 3.0-5.0, because of this i decrease flow, which was very slow to begin with, about 90 drops a minute. The nitrate level ive started with is very high so does this very high nitrite corelate with that? or is this 5.0 nitrite level unusual? is it just cycling?
Any help is much appreciated.

 

[Paul B]

but its still spewing out VERY HIGH nitrite readings, like 3.0-5.0,

The nitrate in my reef has never been that low, I don't think it was ever lower than 10. Now I want to keep it about 15, no lower.

 

[c griseum]

Paul thanks for responding but i think i confused you. The device is just starting to lower nitrate which is at a very high rate in the vessel im cycling it in. But i meant NITRITE is spewing out in such a large volume 3.0 -5.0 ppm. NITRATE is coming out at about 10 ppm lower than the 60 ppm that went in.

I was hoping you could tell me whether the very high nitrites coming out of the device three weeks into cycling are normal. The nitrate is starting to be consumed by the device by very small amounts. The flow is slow. Should it be producing so much nitrite?

Thanks for getting back to me so fast!!!

 

[c griseum]

I just realized you commented about not having test kits. i know you said yours started to work very fast, about a month. Im coming up on a month and ill see if the nitrite stops. If not ill have to redesign it and try again.

 

[Paul B]

But i meant NITRITE is spewing out in such a large volume 3.0 -5.0 ppm. NITRATE is coming out at about 10 ppm lower than the 60 ppm that went in.

OK, my fault. They should change the name of "nitrite" to something like "Red dye #2 or something like that. Nitrate and nitrite are just too similar for a chemical in the same hobby. Don't you think?

NITRATE is coming out at about 10 ppm lower than the 60 ppm that went in

That is actually pretty good for a new unit. At first mine was working almost 100% but it shouldn't have been and I can't explain it but now my tank is about 40 and the water coming out of the unit is 20, so it is working, but not as efficiently as I would like.

If not ill have to redesign it and try again.

Thats the name of the game, keep redesigning. The thing should make nitrite right away as that is the first step in denitrification. That should change soon and no nitrite should be produced at the outflow.

 

[c griseum]

haha yes the one letter difference between nitrite and nitrate doesnt suffice the toxic difference in substances. They should definitely rename one of them LOL.
Sorry about the confusion.
Tested my device again today and the nitrite is still very high. Much the same as it has been. High nitrite and a small consumption of nitrate. Have the flow through the device even slower now. probably around 15 minutes to flow all the way through and maybe 60-75 drops per minute.
In a few weeks, if there's no change, its time to rebuild.