Denitrifying coil works like a charm

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I built a few of these over the years and was not crazy about any of the designs but this one I made last month works 100%.
My reef now has a nitrate reading of 40 and I figured it would be a good time todesign a new Denitrification device but I had no idea it would work so good and so fast. They usually take a couple of months to fully work but I had it running for a month and I just tested it. Water going in has a nitrate reading of 40 and with just one pass through the device which takes about 10 minutes, water comes out with zero nitrates. Not one or two, but zero. I never thought the thing would work so well and as soon as I get time I will install it on my reef.
I have some reservations about lowering my nitrates now, which seems wierd considering what everyone thinks about nitrates but for some reason, my tank never looked so good and the corals were never so big. SPS, LPS and leathers are growing faster than I have ever seen them grow.
I doubt it is the high nitrate levels but I wish I knew what it was. I may just install the Denitrification coil for a little while to slightly lower the nitrates to see if it affects the growth rate.
I have been cycling the device with Vodka.
It only processes about a gallon an hour or so but I will measure it exactly when I have time.
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great idea. I used my first one on my first nano in about 2006.30 m of 6mm tubes with water pushed by a 450lph powerhead and the flow rate regulated by a valve. Just make sure that your water doesnt smell of sulphur when the water exits tube otherwise it messes ph up. Just increase flow rate a little to avoid sulphur buildup
 
Glad to hear you got it to work well, i also built a diy one previously, but i never could get it to work properly... Always had a nitrate reading with the outlet water... Even dosed carbon to help process, but no positive results (ran for 3months in a seperate "test" tank)
 
Paul this system works very well. Used it for a few years. The big trick is to get right flow through to the amount of carbon dosed. You can actually control the Nitrate level you require in your tank by adjusting the flow through and carbon feed. So if you want a 5ppm Nitrate level just dial it in. Or a 1ppm nitrate level. Brill.
 
That sounds cool. This thing has a very slow flow so I doubt it will reduce the nitrate in my tank to zero, I also don't think I want to. It is just an experiment and I love to experiment.
 
Great great great, i do wish one day i have the privilidge to visit you and chat
 
I am putting it back together with some tweeks and I will start cycling it again. I changed the flow from bottom to top just to make construction easier and I added 2 air vents and test ports. Right now I don't want to lower the nitrates too much because for some reason the corals are growing very fast. I have a giant mushroom that for 5 years was a tiny mushroom looking thing, now it is close to 9" across and it grew in a few months. I am afraid to feed the thing because it is taking up too much real estate and is covering some neighboring corals which are themselves getting too large for the tank.

This shows some of the internal parts, two of the tubes are inside other tubes and are not shown.
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I am cycling it again now and when it starts to work I will install it. This is a view from the inside top.
Those tubes let out the air and I can test the water in different parts of the thing to see which part is doing what.
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Cool diy, I am building something similar at the moment.
What is the point of the 4 pipes?
How do you dose the vodka into it?
 
There are actually 6 pipes, two are inside the ones shown. The purpose of the pipes is to have surface area for the bacteria to live. There is no bio balls in it. Bio balls would allow some short circuiting of the water. The tubes are all sealed on one end and the sealed end is inserted into the next larger tube. The water must flow through the entire length of all the 6 tibes which provides a large surface area. The small black tubes are to let air out on the initial filling and I can test water in different parts of the device. I don't want to reduce nitrates lower than 15 so I will remove it when the nitrates get to that point and build a smaller one. You can build this in 2 hours for about $20.00.
It is now running in a small container, and I dose vodka in there
 
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These things work very simply. The 40' of coiled tubing grows aerobic bacteria inside which uses up the oxygen in the water. The de-oxygenated water then flows the full length of all the 6 pipes which are inside each other and each pipe is capped on one end. Some units use bioballs or some other material that bacteria can grow on. Bacteria can grow on anything and you can put rocks in it if you like.
Anyway the bacteria that grows on the pipes, or bioballs are anerobic bacteria and they process nitrate but only in the absence of oxygen which is the reason for the tubing.
The water comes out completely devoid of nitrates.
I did not invent the thing, they have been around a long time.
 
These things work very simply. The 40' of coiled tubing grows aerobic bacteria inside which uses up the oxygen in the water. The de-oxygenated water then flows the full length of all the 6 pipes which are inside each other and each pipe is capped on one end. Some units use bioballs or some other material that bacteria can grow on. Bacteria can grow on anything and you can put rocks in it if you like.
Anyway the bacteria that grows on the pipes, or bioballs are anerobic bacteria and they process nitrate but only in the absence of oxygen which is the reason for the tubing.
The water comes out completely devoid of nitrates.
I did not invent the thing, they have been around a long time.

thanks for the reply Paul, I understand now why flow is so crucial,
 
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