Fluval 306 problems

[raiderdave]

Fluval 306 problem. Approx. 5yrs old, lately cavitation noises which eventually leads to pump shutting down. Upon inspection, the impeller cover dislodged from mount. Thorough cleaning of pump head, still an issue. Hagen rep. advised replacement of impeller & shaft, impeller cover, rubber head seal $45.00. Not a fix, within minutes with new items installed, same cavitation noise, pump shut down, impeller cover dislodged. There's a tiny yellow tube next to impeller well, thought to vent impeller well. Clean it, hogged it out...seemed to be the fix. However, months later its doing it again. So...now the fix is to wedge a small piece of plastic into impeller latch to keep it spread wide, forcing it to stay tight in its mount. I have no idea what is causing this cavitation issue. My fix is a band-aid to the real issue. Any ideas?

 

[Andrewtfw]

I don't know if this is the cause you are experiencing. When I had 306 and earlier models of the fluval canisters, I frequently had to replace the impeller cover. It is the gray one with clear clips. They would break off as I would remove the cover from the head unit. I assume there were hairline cracks leading to the separation. Perhaps this is what you're experiencing. Are there any signs of damage to the impeller cover where it clips into the head unit? Newer covers were redesigned to correct this.