"Cleveland Ponder" wrote in message
om...
I have my skimmer and bottom drain both going to a stock tank which
acts like a settling tank/pre-filter. The pump draws from the stock
tank. The top edge of the stock tank is a few inches higher than the
normal water level so it is a gravity feed to the stock tank from the
bottom drain and skimmer.

I am confused...if the stock tank is above the water level...how is it
gravity fed? Or did you mean it spills back into the pond via gravity?