Coil Denitrator questions

I have 3 separate tanks, one a display-style refugium with 5 consecutive sectinons. The water in all of these totals 110gal. I'm looking to build a coil denitrator, but have some questions. And yeah, I've read the other threads about this, but some things are still unclear.

1) What drip rate is best for water returning to the tank? Someone said 80 drops per minute until nitrates are zero, then 160 drops per minute. Is this a good rate?

2) And how should I power the denitrator so as to get around this drip rate?

3) 25 to 50 feet of 1/4" tubing will ensure that the water becomes anoxic, correct?

4) Is there an easier way than eternal tubing? I mean, tubes have little surface area compared to bioballs and such, so why do we rely on the tubing alone to harbor bacteria which make the water anoxic?

5) Commercial versions have opaque housing. Is this necessary for the anaerobic bacteria to survive/do their job or something? If possible I'd like to build a transparent CD so I could explain to people how it works. Even if it does get all gross-looking inside.

6) Once the water exits the length of tubing, how large should the area with bioballs be, and how many bioballs should I get? I know, as many as possible, right. But I don't want to make this thing unnecessarily huge...
--I just saw something saying that algae will grow if there is any light. Dang. Algae uses visible light, right? Someone mentioned UV-resistant tubing, as if algae utilizes UV somehow... Is there possibly a different design that may allow me to build a CD that you can see how it works? This is fairly important to me, if this would be possible.

 

Nobody knows anything about these? Come on! This is 3reef!

 

Sorry, while there have to be a couple, I don't think too many are currently using a coil. Most have gone with DSBs to denitrify their tanks.

 

I perfer a fluidized bed reactor.

 

1) What drip rate is best for water returning to the tank? Someone said 80 drops per minute until nitrates are zero, then 160 drops per minute. Is this a good rate?Drip rate of 80 p/m is good to start out, however I started out at 60, and will move up to just about to a constant flow but still a drop when my Nitrates reach 0.

2) And how should I power the denitrator so as to get around this drip rate?I am using a mini-jet 606 with a JG mini ball valve to change the rate of drip.

3) 25 to 50 feet of 1/4" tubing will ensure that the water becomes anoxic, correct?I went with 40' but 25' would be fine as long as you are not pumping in a lot of air bulbs to begin with.

4) Is there an easier way than eternal tubing? I mean, tubes have little surface area compared to bioballs and such, so why do we rely on the tubing alone to harbor bacteria which make the water anoxic?The tubing is not to harbor bacteria, the tubing is to allow as much Oxygen to be removed from the water causing the anoxic state.

5) Commercial versions have opaque housing. Is this necessary for the anaerobic bacteria to survive/do their job or something? If possible I'd like to build a transparent CD so I could explain to people how it works. Even if it does get all gross-looking inside. Opaque housing can be used, one of the main reasons why we dont is for the design. With the commercial units you can take them apart and clean them out. With the DIY depending on how you make yours it will be all glued together and you will not be able to clean them out. Also Commercial units can be converted to a calcium reactor when your nitrates are gone.

6) Once the water exits the length of tubing, how large should the area with bioballs be, and how many bioballs should I get? I know, as many as possible, right. But I don't want to make this thing unnecessarily huge...The amount of Bioballs does not matter as much as flow rate. With a 25' line you can have a 1' high tube with about 30BB (small one) or you can have 2' high with 50' tube with 60BB it all matter on the quality of the Bioballs and the flow of water. Keep it to the 80/160 and you should be fine.

--I just saw something saying that algae will grow if there is any light. Dang. Algae uses visible light, right? Someone mentioned UV-resistant tubing, as if algae utilizes UV somehow... Is there possibly a different design that may allow me to build a CD that you can see how it works? This is fairly important to me, if this would be possible. Like stated above you can have a clear design as long as you are able to open it up and clean it out. You can also make the clear design and have the unit covered from light and still be able to show how it works. Create a coffin for the unit and you should have no algae growth.

Good luck and make sure you post some pics. I will try to get mine up ASAP!

 

Thank you for the info. berlin Joe... very informative!

 

A fluidized bed is aerobic. Different deal.

 

But a coil is anaerobic? So a fluidzed bed filter would be like bio balls(nitrate factory?)

 

I've used Rainbow Lifeguard fluidized beds for years. I still have one on my 55 hospital. FBs are great for breaking down amnonia. I don't believe that they or bio balls are a nitrate factory. It's a bum rap. The issue is to denitrify all the way to Nitrogen gas you need an anaerobic process. There simply isn't enough energy in the process for aerobic bacteria to break nitrate down for food. Because of the high flow rates involved, FBs or bio balls simply don't handle that portion. One needs to supplement FBs or BBs with either a DSB, Live Rock, or a denitrator to handle that segment of the nitrogen cycle.

 

More info on this old thread:
http://www.3reef.com/forums/i-made/coiled-denitrator-diy-29402.html