So I quick google sketch-up'd this setup. Any constructive criticism is appreciated. All this stuff is pretty much to scale. That's a standard 50 gallon tank dimension. The strip across the top of the divider is an acrylic piano hinge that I've got laying around. The acrylic nubs sticking from the walls in the first chamber are to hold egg crate with carbon, filter sponges and any other chemical/mechanical filtration I want. The water falls from the overflow slits down through these and under the wall to the right. The skimmer is a Berlin Classic rated at a 250 gallon tank that I have in my garage. The pump to run it is a Rio 2500 which pushes about 750 gph through the skimmer and directly back into the tank. The top of the tank has a cut out just big enough for the skimmer cup to slide through.