Andretti,
My frustration led me to contact Hagen Corp via email. I got a reply from them and sent another response. Below are the messages: It might be worth it to send them some email - maybe there is a problem they need to know about.
Request : I have a Fluval 404 filter that has been in operation for 14 months. I recently added a phosphate removal medium to one of the baskets and since then there is an occasional burst of air through the output nozel into the aquarium. I have checked the motor seal ring, hose connections and self primer assembly connection and can't find any leaks. The air is flowing through the entire unit and makes noise when it does. The cannister is not located completely below the bottom of the aquarium level. The top of the unit is about 5" above the bottom of the aquarium. Could this location be the cause of the air build-up? Can you suggest any other reason for this? Thank you"
"Dear Kate,
Do you run any air pumps in your aquarium? If so, how close is the air output to the intake of the Fluval? Do your hoses run straight from the top of the aquarium to the top of the filter, or is there a bit of slack? When you primed the filter after adding the phosphate remover, did you start with the canister empty, or full of water? Also when priming, was the output nozzle above or below water level? Please reply.
Thank you,
Sharon Emond, Customer Service Dept.
Rolf C. Hagen (USA) Corp. "
"Dear Sharon,
Thank you for the reply. In answer to your questions, there are no air pumps but I have two power heads, one on each side of the 55 gal aquarium, mounted in the top rear corners, the Fluval intake is in the rear center of the tank with the end about 1 inch above the substrate. The hoses run from the top of the tank to the to of the Fluval, but my canister is not placed below the tank, it is off to the side and there is a little bit of slack. After I added the phosphate remover, the canister and hoses were still full of water, very little priming was needed and the output nozzle was below the water level. Our tank is set up on the 4' X 6' landing of our stairwell, 3 steps above the floor. I originally had the canister placed on the step below the landing, which put the top of the canister about 5 inches above the bottom of the tank. After reviewing the recommended set up again, I moved the location of the canister to the next lower step, placing the top of the canister at the same level of the bottom of the tank. This seems to have helped the problem quite a bit, but not completely. I am thinking the filter needs the additional assistance of gravity to feed properly. I will move the canister to the floor level, which will place the top of the canister below the bottom of the tank and see if this ends the air bubbles. If there is anything else you can recommend, please let me know. Thank you."
