so i have a bio wheel rated for 55 gals. it started really good and ran well for about two months. now the wheel always stops rotating i clean the wheel and backing all the time and still doesnt work, almost more water comes out of the overflow hole then the filter (i also change and clean the filters regulary.) and Im doing regular maintnace on the prop and motor. I have never had any problems with my auqua clear in my mind they are No. 1 in hang on filters.