overflow box and return pump

[marlinmero]

I was wondering how you get the two to balance out? do you just use ball valves on the overflow box to slow down the incomeing water to match the pump?

 

[DonW]

The other way around. Valve the pump.

Don

 

[luke33]

If your overflow can pull down up to 1000gph and you put a 700gph pump on it your overflow will just pull 700gph. If you put a 700gph overflow on and a 1000gph pump, you will have a tank overflow and a dry sump. The overflow will adjust with the return pump unless the return pump exceeds the overflow capacity.