Join Date: Jan 2006
Location: Burnaby, BC, Canada
I think each unit and each person's experience is different. I've seen this AC vs. Emperor debate on every fish forum I frequent. The overall conclusion I draw is that the quality control of HOB's are terrible, so that getting a quiet one vs. a loud one is a hit and miss affair. I happen to have had an AC mini, AC500, and currently am using a Penguin 100. The AC mini was silent, and so is the Penguin. The AC500 made a terrible racket almost 24 hours a day. The lid rattled, the impeller clacked, and I couldn't get rid of the splash because it was on a 125 gallon where the rim was too thick. Anyway, I think the only way to ensure you get a quiet one is to get one and return it if it's loud and try another....or get a canister.
Filstar pimp #59 (shhhh on the Eheim)