Scale is out of whack as I have not measured anything. I am thinking no elbows in the tank, just the bulkheads. 2.5" from the back of the tank to the front of the "box", then have the box placed just under the lowest bulkhead, and divide the thing in half so that water will be able to get to the high hole. The braces can go in the box under water level (maybe half inch to an inch) The braces being there should strengthen it and alow me a ledge so I can lay a piece of eggcrate over top and not need strainers (I hope). (braces on outer edges of the box are missing in the picture as I am not so good with google sketchup)
I am thinking of plumbing it with external dursos like Dephinus has in his fw tank.
Thoughts?