There are people that'll recommend the "Durso" because they just don't get that there's a difference...When you have a hang-on overflow, like you do, the Stockman standpipe, which is a variation of the Durso is the one to use on the overflow to silence it. This was told to me by Durso himself when I had the problem. He said that his design is too big for the hang-on kind of overflow, of which I have two 600-gph overflows. It's really easy...If I could do it, I'm sure anyone can...It's been six years now and not a sound from my system....Alan