I have a 55 gallon freshwater aquarium for tropical fish. I only use overflow water filters (hangs on the back of the tank). I’m not interested in a canister filter or anything overly complex. One of my old “Cascade” water filters recently bit the dust, and I’ve been trying to find a good replacement. I started by buying the “Emperor 400″ with a dual bio-wheel. It was too noisy, so I returned it. Then I got a Whisper 70, because they’re supposed to be known for being quiet. Guess what? It’s noisy, too! I don’t mind the sound of the water flowing. That’s fine. It’s the electric noise that bugs me! It’s like a constant grinding of the motor or the impeller or something. I hate it. My Cascade is completely silent in that respect, despite the fact it’s over 15 years old. Problem is, none of the fish stores near me sell Cascades. I just want something that is cheap, works well at cleaning the water, easy to use, and is quiet. Please don’t suggest a Penguin 350, because I hear that Penguins are noisy, too.