[tbittner]

My big tank is the same way, JoJo. I'm going to use two of the 1" holes for the return from the sump and all the rest of the holes (6 3/4" and 3 1") for the closed loop. The three 1" will feed the pump and the 6 3/4" will be the return.

I'm going to user my lifereef overflow boxes to get water to the sump.

While the snapper is lower volume, you'd need to use probably 3 of them, at least, to provide it enough water to prevent cavitation and bubbles.