hi all...i dont know if i can get some answers here...but its not for the nano tank tho..
i am trying to set up the wet dry for the big tank..
the tank is not rr so need a overflow...
i am gonna get a cpr overflow...but kinda dont know which one to match the pump...
the pump does 1200gph, but the headheight is 5 feet, so it should only pump out 800gph according to the chart of the pump...
the wet dry is only for a single bulk head, but i have 2 socks, which i think i can do a dual overflow, just run 2 bulkheads, and tie the other one to the sump..they have a dual overflow that is for 1200gph, with 1" bulkheads.
or they have a 800gph single overflow or even a 1600gph single..should i go with that?
would a 1600gph single better? or i have to match the gph of the overflow with the gph the pump deliver?
thanks all.

You can always put a ball/gate valve on the pump output to dial it down a bit, or tee off the return line and dump some of the excess return right back into the sump, again, with ball valves to control how much.