I wish that was possible the room behind the sump is the furnace room and it is very small I am actually pretty happy with the design and think the overhead sump will be a great feature to show off now. When I have company over my wife starts showing them our fish I usually rip open the bottom of the tank to show them my plumbing and sump guess I am jsut one of those guys lolPotts050;3558998; said:1/2" G1S Fir sheeting would be fine but I would recommend marine grade if your willing to spend the money. I was thinking do you really need the overhead sump? If your going to hide your pump and other mechanical why not move everything into the room behind the wall. Make a corner of the pond a little shallower for your mangrove swamp, and put some caves under it for fish that want to hide once in a while.