I have 2 2.5 gallon tanks in my bedroom with a sponge filter in each. One tank has my betta and the other has 2 longfin black skirt tetras. The air pump is a tetra whisper 60. The sponge filters have gravel in the base and then have sponge on top of that and i cleaned out the plastic air diffuser and now they are creating too much water movement. I am going to get valves to limit the flow, but could that damage the pump? Is a whisper 60 overkill? I use 1 air outlet for each tank.