I just built my first sump/fuge. I got a 300GPH overflow from eshopps, a 20G sump and a mag 7 return pump. First thing i noticed when i fired everything up was the pump vibrates like crazy and the base it came with doesnt have suction cups to hold it still. I have for the time being siliconed on 4 suction cups to the pump and will hope it holds. I also noticed my overflow "gurgles" alot. the problem i see with the overflow is that it has the sponge filter around the exit of the overflow and a piece of 5/8 PVC pipe that drops into the exit half way down so that the remainder that sits inside the oveflow will support the sponge and keep it in place. When i take the sponge and pipe out so its just is strait down the noise goes away for a second because the water can drain out solidly with no air if that makes sense??, but now the oveflow can drain faster and soon the water going out is faster that water going in, and the gurgling starts again. i some how need to make this quite or the whole sump project will have to be scrapped because my husband can't stand the noise the new setup is making. i really dont want to get rid of it but it takes away from being able to enjoy it with all the noise. Any suggestions would be appreciated. not sure it makes a difference but the return pump i'm using is a supreme classic by danner??