One thing you will absolutely want to do is place a PVC gate
valve (not ball
valve) in the 3/4" return line. That way, if you happen to have a pump that moves more than the drain can handle, you can reduce & fine-tune the return flow....... otherwise you will have a flooded tank & very wet floor. You want to place the valve on the output side of the pump (between pump & tank), not on the input side of the pump. Restricting the outflow is OK, restricting the inflow is very bad for the pump..... causes sucking and cavitation, which is detrimental to the motor & impeller.