I have acf`s in with my fish 30 gal.. All is good. But my question is a filter... What is the best filter for quietness. I feel bad because I hear the noise from the motor. I had a whisper 40 internal filter which was some what decent untill it got loud after 6 months. So I went out and bought a more expensive one today, a fluval aquaclear 20-50 This is the loudest I have ever had.So disappointed. I took it back & now got a quiet flow 20 & it is very loud. I can not have this on for them poor frogs. I need help with a filter. The tank just vibrates/humms