People who have aquaclears,

I have 4 ACs and they are wonderful. They only make noise if the lid is not on right or you may hear the water splash if your water level is low.....
 
I completely agree with all the above posters. I have 2 AC50's on my 33g long and when I keep up on the water lvl being up to the lip of the filter, I can't hear a thing. Other than when I don't have the lid clicked in right, then that rattles like a mofo. Others have mentioned putting things on top of it, but I usually find when I can hear it all I need to do is push it down in place a little better and over the next half hour it will settle itself and not make noise.
 
I agree with what others have posted.

I have several of them and they are all quiet.
 
I've had mine for at least 3 or 4 years, sometimes it acts up, I take the lid off and that does the trick, or put something on it like the others have said.

A few times it's been rattling in the pump, but a swift punch sorts it out.
 
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