[Rakaal]

Im hoping someone has a good fix for this as this is becoming quite frustrating.

I have a Fluval 406 cannister with a carbondoser ext5000 CO2 reactor attached in the outflow line.

Picture attached

Whenever I disconnect the filter housing, for cleaning, hose maintenance, etc.. i get air in the line somewhere, I'm assuming this is not abnormal.

My problem is trying to get the filter to restart. There is an obvious bubble between the outflow of the cannister to the intake of the reactor. The primer of the Fluval seems to be of zero effect.

I had success starting it by 1) filling the cannister manually, 2) taking off the sprayer in the tank and putting it in a bucket, keeping it below the tank, this created a siphon.

I also had success in turning the pump on and then using the priming plunger like mad, which eventually started the pump.

Dropping the tank outflow into a bucket was somewhat of a pain, and I'd prefer not to repeat it. Turning the pump on prior to the lines being filled with water seems that it would be hard on the impeller. Neither of these options seems like long term fixes.

Does anyone have a surefire method for this situation?

 

[loach guy]

The issue is that your reactor is lower than the output of your filter, therefore your CO2 bubbles are working their way back upstream. Mount the reactor to the "ceiling" of the stand and shorten the hose going to it. Bubbles always want to go up. Let the physics of that work for you, not against you. Good luck!

 

[d33pVI]

Empty all water from the outflow tubing and reactor prior to reconnecting the aquastop to the canister. As long as the intake line is still filled with water the system should start the siphon and refill as soon as you push the lever back into place.

 

[bluecheese]

I have the same issue with my fluval 306. I've found that removing the strainer from the inlet tube, then lifting the tube to allow the water to flow into the filter helps. Then I prime it and plug it in. It should push any air out of the outlet at this point. You just have to make sure the syphon is not interrupted on the inlet side; its not as important on the outlet side.