HFP75's - 55 Galllon

[hfp75]

My tank is about a year old. The chronic PO4 and NO3 are forever the issue.

I have a reactor that I run some Carbon and RowaPhos in intermittantly and some Chaeto down in the sump under a light.

My NO3 hover consistantly 40-60..... water changes work but only for a day or so and then back to 40-60. They dont go over a 60 even if I dont change water for a while.

So, I got thinking. I need a source of anaerobic bacteria to thrive on my NO3. I have decided to build a de-Nitrate Coil. Pics and progress will follow.....


Tank
http://i101.photobucket.com/albums/m...ps16b93732.jpg

Sump
http://i101.photobucket.com/albums/m79/hfp75/sump3.jpg

[hfp75]

So, Today I started working on my Coil. I am using a 3' x 4" PVC pipe. Generally, what I have read online is that its 2' but I have added an extra foot or 50% of capacity which should mean that I eventually could run it abit faster and still be ok.

My coil is 3/8 OD 1/4 ID semi-rigid tube that was a PITA to get coiled into the 4" pipe. Once again most directions talk about 50' and I'm using 75' another 50%. Here is a pic.

http://i101.photobucket.com/albums/m...ps24dcc06a.jpg

I cut a hole and glued in a double female threaded adapter that I need to make sure doesnt move as it is gonna be more of a bulkhead. This is the 'Tank Water IN'. Pic...

http://i101.photobucket.com/albums/m...ps16abf657.jpg

To add some strength to it I added the end flange over top the normal pipe at the adapter. It is a snug fit and well PVC glued in place.

http://i101.photobucket.com/albums/m...ps82a5800f.jpg

To ensure some more strength I have JB Welded the outside with a good sized application. This is kinda visible in this pic.

http://i101.photobucket.com/albums/m...pse203dd32.jpg

Here is a shot of the bottem. It is a threaded end cap. Just in case I need to get into this thing. Inside at the top I added a 90 degree elbow to the end of the 3/8 / 1/4 tube, just to make sure the tank water comming in heads to the middle. This elbow narrows the ID just a bit more and I am not sure about this. This is the narrowest Diameter of all the tubes (the bottleneck). If I need to remove it I can since its on the threaded end. The flow shouldnt be much either so, in theory it should work.

http://i101.photobucket.com/albums/m...ps8a856665.jpg

Its drying over night.

[IanWR]

Very interesting! I had never heard of a de-nitrifying coil so had to look it up. I'll keep up on your progress.

I have a question about your sump. I see a bag of ceramic rings, is that the drain that goes into it? I'm still very new at saltwater, but "they" seem to say to avoid biomedia as they came become "nitrate factories". Could this be contributing to your problem?

- Ian

[Kryptic4L]

is that a uv sterilizer ? is it possible that its killing some good stuff ?

[hfp75]

Ill be doing a water change today and a cleaning. I'll remove the media from the sump and give it a vacuum.

The UV is a 9watt and has been turned off for the last few months - the light burn out. No changes to the NO3. Last week I replaced the light and got it turned back no and again no changes so I'll rule out the UV...

[Kryptic4L]

also you might want to do some googling about ceramic rings, as it appears you have a large amount of them in your sump. Alledegely they can become nitrate factorys if not maintained.