Originally Posted by francis
Well is your overflow draining too fast or is your return pump too strong? If draining too fast then get a stronger pump if the other one then maybe add another ova outlet to drain the water?
the overflow rate is only governed by the pump rate,what you have failed to mention is the pump must be matched to the overflow gph
rate,or you will have trouble and noise.if your overflow can handle 600gph then the pumps rate after headloss must be slightly lower at lets say 550gph,if you dont match this it will be nand the flowrate going through the overflow will not be strong enough to force any air bubbles around the pipes and so a collection of air bubbles means air break and flood.