aqua clear 500 problems
 

I used to use this filter on a freshwater tank. It sat for maybe 3 years, and I setup a fish only tank and was planning on using this filter. I cleaned it out, and now i notice that its pretty loud while on. The stream of water looks to be flowing correctly. Are these normally loud(i can't remember). Does the propeller get loud after alot of use? I might buy a different model, because this tank is in my room and i can with an air conditioner going, but this is unbearable.

have you pulled the impeller to see if it is damaged in anyway...it could be off balance..

is it loud vibrating noise or loud humming?

clicking, clunking, chattering would all be related to unbalanced impeller