The top edge of the stock tank is a few inches above the water level.
See ascii art below. the tank is approximately 22" deep which would
put the bottom 18" - 20" below the pond water level. With the 4"
pipes from the bottom drain and the skimmer attached to the bottom of
the stock tank the water comes in to the stock tank at about 6psi.

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"BenignVanilla" wrote in message ...
"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?