OK I have got the bouncing part figured out. Now the overflow works wonderful, is quiet, and maintains the water level without bouncing. Heres some pics. Keep in mind this was just a quicky rig so the finished system is yet finished. Basically by adding a length of air hose, right at the top of the intake, the air taken into the overflow is controlled and eliminates the bouncing effect. The pics are of a 1-1/2 inch pvc overflow. You can see the blue air hose pulling air in on one pic. By the way this size overflow rocks. The pump in the pic is pushing 1100 gph at that head and the overflow has no trouble keeping up. Basically this solution is like the stockman or durso standpipe modifaction. My next step is to create stockman adapter and see if this works as well as my rig here. By the way this can be made as a top surface overflow or a overflow that pulls from lower in the tank. As I finish the working one I will post pics. Hope this is helpful.
Seriously though I think my idea is doable. Basically I'm trying to tune the siphon not cut out the noise. Mine is already very quiet and I'm running over 1000 gph threw it. The stockman is an modification to add to bulkheaded overflows in reef tanks. Basically and add on similar to what I'm trying to accomplish where you can tune the siphon by controlling the air in the overflow thus eliminating the flushing or bouncing effect. Its very similar to a Durso standpipe. I love playing with DIY stuff!!
