Who Gives A Fish Forums

My external filter's been making a weird grinding noise for the past two days. It's a Fluval 307, about a year old. Water flow seems reduced, but the media's clean. Any ideas what's up?

Sounds like the impeller might be clogged or worn out. Had a similar issue with my Eheim last month. You try taking it apart yet?

Yeah, impeller's usually the culprit. Also check if the intake tube's got gunk. My canister was acting sketchy till I cleaned the tubes.

stormbolt wrote: ↑Wed Jun 11, 2025 10:58 am Sounds like the impeller might be clogged or worn out. Had a similar issue with my Eheim last month. You try taking it apart yet?

Not yet, gonna crack it open tonight. Anything specific I should look for?

Look for cracks in the impeller housing or debris stuck in the blades. Sometimes a tiny bit of sand or plant matter gets in there and messes with the rotation.

And if the impeller's fine, maybe the motor shaft's dirty. A q-tip dipped in vinegar can clean it up real quick. Just don't force anything.

bluemuse wrote: ↑Fri Jun 13, 2025 3:19 am And if the impeller's fine, maybe the motor shaft's dirty. A q-tip dipped in vinegar can clean it up real quick. Just don't force anything.

Yep, vinegar works wonders. Just rinse it well after, don't wanna mess with the water chemistry.

Thanks for the tips, guys. I'll report back after I've checked the impeller and shaft.