Rena xp2 filter impeller no longer spins when canister is put together.

I have a Rena Filstar XP2 filter over the past week it hasn't been working at all, the impeller spins fine when I have it just inside the top part that I'm guessing is where the motor is, but when I screw in the impeller cover and place it on top of the canister it will no longer spin. I've completely cleaned the unit two or three times, including the tubing and all pieces completely. I've read most of the questions/answers on here and nothing has helped, I've primed and re-primed as well as checked meticulously for air leaks as well as re-sealing the tubing and all connections. Please help, daily water changes are becoming frustrating and this filter has given me nothing but problems since day one.

A: I'm very sorry you are having so many problems with your filter. From what you describe it sounds like the impeller cover is binding on the top of the rotor/impeller when the cover is locked into the bottom of the motor. The alternative is that the impeller cover is not locking into the bottom of the motor or is actually loose and not stabilizing the rotor/impeller so that it will spin correctly. If this has been something that has not worked from day one then you probably have a defective motor and you should contact the manufacturer for a replacement. The manufacturer is Mars Fishcare.