fatman you are absolutely correct, you told me that before and i didnt listen hence i spent my entire weekend replumbing my sump
i had way to big of a pump, i had the flow cut back so much with a ball valve that i actually blew the pvc connections apart (they were not glued but still shouldnt have had that much pressure on them)
anyway i got a smaller pump rated at 600gph at 0 head height and it is working much better and is running wide open, im getting much smoother drainage from my overflow and im making up the difference with powerheads
oh and yes im going reef tank