Okay. I've got lots of questions again tonight. As I have posted before, I'm running a Whisper 30 (145 gph), an Aquaclear 200 (200 gph), and an undergravel filter without power heads in my 29 gallon tank. Can you have too much filtration in a tank. The water is moving a bit but it doesn't seem excessive. I have 6 redeye tetras, 4 black phantoms, and 3 corys.