Koralin Biodenitrator Challenges

[Donmarco]

I have a 4.5 yo 125G reef tank with a 35G sump. Three weeks ago I installed a Koralin Biodenitrator below the tank, next to the sump and am using a small doser pump to supply tank water siphoned in from the sump and then returned to the sump near the return pump. At first the biodenitrator worked flawlessly but about a week ago it started malfunctioning. Several times a day the small doser stops pumping water into the biodenitrator and the effluent goes dry. I've tried several things. Usually what works is that I shut off the Eheim pump on the reactor, close the effluent and open the air release valve. The chamber fills again with water. Then I close the air release valve, open the effluent and turn on the Eheim pump. The moment I do the doser stops drawing water again and the effluent goes immediately dry. I can see air bubbles which move up and down through the air tubing, both on the intake and the effluent. When I eventually get things working again, it works only for a short while and then the trouble recurs.

 

Might anyone have experience with the Koralin? Does anyone know what may be causing this and how I might correct it?

 

I've read in another post that someone vents excess CO2 from their reactor into the protein skimmer. Might this be the problem I'm experiencing, an excess of CO2? Would venting it continuously resolve the problem I'm experiencing? If so, might I presume the way to vent is to remove the air release tube from the top of the reactor and run air tubing from it to my protein skimmer? If I do this won't water from the reactor overflow into my protein skimmer? I've noticed that when the air release valve and effluent are both open that the water level drops drastically in the reactor and continues to fall until I turn off the Eheim and doser pumps.

 

Thanks for the help.

 

Mark