于 2002-04-13 22:28 Kenny: All problem had been sloved already loo . I made the flow-in hole a bit smaller then the water flow to sump become slow d and without noise. You are right! I'm using 40RX, I feel that is a great return pump. Now I fill my tank with fresh water and run it overnight, tomorrow I will go fs buy two bag of sand and refill my tank with salt water.