Fluval 405 air bubbles/leak, can't figure it out
I have a 1.5 year old Fluval 405 that is sucking air in somewhere and I can't figure it out. It causes the impeller to rattle and blows bubbles out every few minutes or so when the canister fills up enough.
I first replaced the impeller thinking that was the cause before I noticed the bubbles.
Then I replaced the gasket around the lid and the hoses thinking there might be a crack somewhere on the intake but still no luck.
Today I noticed a little water leaking out from somewhere behind one of the side clamps but I'm not sure if it was due to me shaking the air out of the unit.
Do any of you have experience diagnosing and fixing this? I also have a same age Fluval 305 that is still working perfectly. I don't really want to sink more money into this 405 when it might be more economical to just buy a new canister.