After tearing down and selling a 120 gallon reef tank I had for many years due to a move, I'm getting back into the hobby. I picked up a used 75 gallon acrylic all-in-one tank at a great bargain. My plan is to add a sump in a closet behind the tank's final resting place. I am brainstorming the best way to accomplish this, while possibly using the current set up for some sort of additional filtration (vs just making it a huge overflow area). Anyone have any suggestions as to best drain setup (bean animal?), where to drill the holes? How to utilize the current configuration in conjunction with the sump (will most likely go refugium route btw)? Any ideas are greatly appreciated!