Return Bulkhead so deep?

[Squiddy]

Ok so I cut a bunch off the drain line and put a coupler in. I just guessed at the length and I think it's perfect the way it is now. The water is just barely touching the bottom of the Euro braces. Is the water supposed to pour over the edges of the overflow box (through the teeth) or are the teeth just supposed to stop fish etc?

I'm going to go figure something out for the return line now. Will post more pictures when I'm done.