People who have aquaclears,

mine must have something messed up because they always make a lo humming\whirring sound.

Any impeller will make noise if on the last cleaning you did not thoroughly clean out the impeller hole and rinse the canister. All it takes is one tiny grain of sand or carbon down there and it will sound like you have mice or a tiny marbles in there. So make sure its really clean and you dont have any torn carbon or zeolite bags.
 
My 110 has a slight hum to it that gets a lot louder if my prefilter sponge gets all cloggy with plant debris, I'm sure it makes the motor work much harder when I don't keep up on plant detail/regularly rinse the sponge...I keep it in my bedroom and it's easy enough to sleep through when it's clean.
 
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