I just switched out my Durso Standpipe for a Maggie Muffler. Here is a link to the muffler. Works great and is very quiet. Takes up a lot less room in the overflow....that is why I changed.
http://www.reefH2O.com/product_p/ov20015.htm
http://www.reefH2O.com/product_p/ov20015.htm