I ordered a 75 gallon tank. Planning on using a 20 gallon Sump. I'm going to have a total of three holes drilled in the tank. Two for the overflow which will be 1 1/2" (shadow overflow box) and one for the return. I plan on putting the overflow in the middle under the brace.
Should I go with 1 1/2" hole for return or smaller? How far from the edge of the glass does the hole need to be? Thanks guys!
Should I go with 1 1/2" hole for return or smaller? How far from the edge of the glass does the hole need to be? Thanks guys!


