Coiled Denitrator DIY

Well we know BL used the venturi on a rio pump for hers. Anybody else want to pipe in and let us know how your powering your CD?

 

Birlady, I am confused, [smiley=confused1.gif]do you have the line going into the coil attached to the pump output venturi fitting? If so, the venturi on the output of the pump is for sucking air into the output not pressurizing a line. This would cause the pump to suck the air out of the coil, not fill it as intended.

I am not real familiar with the RIO pump venturi but I know that is how the venturi on the MJ1200 powerheads work. I guess you could turn off the main valve past the venturi and force the water through the venturi opening...but a lot of back pressure there!! Also the line would pop out of the venturi from the pressure unless it is glued!!

I did a lot of research last night on CD designs and about 3 of the 5 designs I found that I felt were viable, used the clear acrylic and the other 2 PVC. The PVC has the advantage of being solid therefore no light is allowed in, but none of the designers of either style said anything about light other than that the tubing is very dark down inside the coils allowing the nitrate munching bacteria to accumulate in the bottom half of the coil. The CD I am working with has brown tubing that allows no light into the coil and very little if any light is allowed between the coils as I have packed them very tightly and siliconed them together. Most of the designs called for at least 50' of tubing or to build 2 CDs and run them in series.

I am going to abandon my plywood concept for an enclosure and sew a drawstring bag out of black nylon material that will fit the unit from bottom to top. And I think, since I have the stuff laying around I am going to try my original concept of running the unit off the feed of the skimmer. If it doesn't work I can just turn off the self-piercing tap. However, I will need to figure a way to filter the water before it goes into the CD as the water being pumped into the skimmer comes out of the overflow of the display tank. Any ideas on that good people of 3Reef? :-/

I did read that some of the designers recommended an aeration chamber after the water comes out of the CD to help lose the gas that the bacteria form from breaking down the Nitrate, hence your idea, Birdlady, of releasing the output of the CD into to some highly oxygenated water. I wonder if I can somehow release the CD return water into the reaction chamber of the skimmer. There is certainly a lot of bubbling going on in there!!!
[smiley=thinking2.gif]

I appreciate any and all input gang!!

Drew

 

Drew,

Just a word about the concept

In reality it is a bacterial reaction chamber. The last thing you want is any algal growth which would only 'gum' up the works. Therefore the need for complete darkness is necessary
So use the brown tubing but make sure, if you are going to use the bio-ball method that the outer cylinder is totally opaque.

John

 

Yeah, John, that is why I chose the brown tubing, also it is UV resistant and I can bury it in the ground if all else fails!! The back yard has a likely spot. I could use the whole unit to make sauerkraut. ;D

I was also thinking I could use some of that lovely aquarium background stuff that is all black and just run it around the outside of the tube and tape it on. So far I have not run into too much algae problems with my setup because I use RO/DI water, but I know eventually (like tomorrow) it will find it's way into my hermit crabs bellies and the rest of the tank!!

Birdlady, I think all you need to do is turn the valve on the pump around so the venturi is between the pump and the valve. When you dial down the valve it will make the RIO venturi act as an output.

 

Hey DX! Yes, if you look at my pic, I have the venturi hole AFTER the ball valve, therefore, pushing water out, not sucking air in....plus I don't back off the water flow at all. I am letting the pump run full out, thus what does not go into my CD goes into the sump. I did test it out and while it does take quite a while to fill the CD, it does run at greater that the 80 drops per minute. The water comes out in a slow trickle...enough that I need to adjust the end-of-the-line ball valve coming out of the CD.

For a CD the size of yours, I would get the next higher output pump tho.

BTW, what is wrong with the water from the display tank going right into the CD?

I did test everything out, hose stays on the venturie fitting on the pump but you could glue it too. The part comes off of the pump. ;D

 

Birdlady

[smiley=yelrotflmao.gif] ;D [smiley=biggrinbounce.gif]

I've been there...

I don't see too well at 3 in the morning or I would have noticed the placement of the hose. I think you are right about the size of my CD, I'll need to get a bigger pump...if the skimmer pump works then no problem otherwise I guess an MJ900 or RIO600...thanks a lot for the info  

 

BL, I would imagine that you will want some kind of Mechanical filtration to keep debris out of the CD. The 1/4" tubing would probably clog otherwise.

 

I'm not understanding why Drew would need a bigger pump.  Even though the unit is bigger he is still using the same size tubing.  Will a bigger unit be able to handle a higher GPH once it gets established?  I was also wondering about back pressure. I think the longer the tubing the more back pressure you will have.  If this is correct then you will probably need a larger pump.

 

As for the bigger unit, the more GPH, I can't see why not.  More bacteria would be in it.  Here I think the amount of bioballs is what would be important.

I was thinking about 3/8" tubing for when I get mine built this weekend so it does't clog.  Also the pump will be right after the skimmer so hopefully most of the stuff will be removed.  I think I was the one who mentioned airation of the water since it comes back oxygen deprived.  I was going to return the water into the water inlet area for my sump / fuge.

The CD is going to be as tall as I can get in the stand (since I have to buy a 10' PVC pipe anyways, why not just make it huge ).  I got a mag 3 pump to power a phosphate remover, calc reactor, UV, and then the CD.  I figure that should be able to power all 3 "small" units with ease using splitters instead of tapping into  my mag 7 that powers my skimmer or mess with the mag18 I have for returns into my tank.

 

10' of pipe? I don't know about you but the hardware stores around here will cut and sell you any length you want. You sould look or call around before you go buy a 10' piece.