I used the pump from a HOB filter that I dissembled, the suction side is about a 3/8-1/2" in diameter. 100gph, I don't think it's the powerheads it's more of the fact the fish always swim in the two top corners.
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What do you guys think of me taking out my turbo snail? I did a pwc today and I voiced how much poop is on the ground from him! I think he is the messiest in the tank by far, maybe he is doing more harm than good?