you could definitely just run the 1/4 hose going in and out and silicon right around that.
Then you could just put a inline valve on the output tube before it goes back into the tank. that way you could control the output flow back into the tank to a medium rate drip.
I just did the threaded valves cuz it looks cleaner and I had access to a tap and die set.
However, whatever works.
good suggestion though and anyone can do that with a drill..which most of us have.
it would also save you a couple of bucks for the valves..minus the one inline valve.

You don't need the die part :wink: just the tap part. It is a NPT1/4-18 tap and it's not going to be included in the typical tap/die set that you see at Can-Tire. They are fairly inexpensive and the drill size is 7/16". Mine has received a fatal impact with a concrete floor and will be replaced when my brain ram starts functioning again.

Hmmm...I think that the coil delivers low oxygen water to the bottom of the chamber, then the water filters up through the bioballs. Based on this, the holes up top would have to be sealed well, but there would be little pressure against the seals.

I believe that the coil delivers water to the bottom of the chamber that has no oxygen as it was used up in the beginning of the coil. The denitrifying takes place in the later part of the coil where the oxygen has been stripped from the water. The bio balls provide more surface for the bacteria that lives in oxygen starved environment so you get that extra anoxic area for the denitrifying bacteria to grow. Yes the system has to be sealed from outside air and from light as you don't want algae growing.

If I've got this wrong please let me know.

Doug

well i got mine complete. just having troubles with the outlet, at it is leaking. will be re siliconing it and trying again. i just need to figure out how to get the drips into a container to airaid, and then back to the tank, as i have no sump.. Filtration is a Fluvy 404.

have you been keeping track of your levels? any change so far in your amm/nitrite/nitrate? I'm really anxious to see what type of denitrification occurs without a direct carbon supply for the bacteria (sulphur denitrators, etc)

Well, im having troubles with mine. See idont have a sum, and i read several places that the water exiting should be airraided. so i need to fill into another little container that has an airstone in it, and then from there, drip into the tank, only problem is, im not putting a 3ft piece of pvc ontop of my tank. Anyone got a CPR overflow for sale? lol

I don't really think that you need to worry about aerating it.
You are only adding 2 or 3 drips a second, not really enough in my opinion to drop the oxygen levels in the tank.
Neal

I was wondering that, however i decided to get a few opinions from some long term reefers before i figure out how to get it in to my tank.

i was thinking of getting one of those drip things that are on a I.V. and dripping into the inlet of the Fluval and so be it. will try something im sure, and will get some pics and results of the after product as soon as i can.

I've got a brand new overflow that I'm not going to use, it's not a CPR though. Did you consider having the effluent going into your skimmer? If not how about sending it into the intake on a power head.

Doug