Originally Posted by tjm80
If you have a 500 gph
overflow, you really don't want to return water from the sump at 500 gph
. I'd say a mag 5 would be better than a mag 7. If anything caused any obstruction in your overflow or drain pipes you're looking at a wet floor.
Your water turnover should be done mainly through the powerheads from what I gather. If I'm wrong someone let me know!
It doesn't make a difference what pump you use if you have a blockage, it will still overflow.It is a good idea to throttle back pumps as it helps prolong the pump life.You also need to keep the flowrate going through the overflow box as high as the box allows so the flow will drag any bubbles through the box to the other side low flow wont do this very well and can cause floods.
As for turnover,everhting is taken into account,flow through the sump depends on what type of sump you use,fuge,macro