Sump Design

[trilinearmipmap]

Here are the things I would do different about my sump if I were doing it again, hopefully some of these might help you.

First you want as much directly overflowed water as possible to go right into your skimmer pump intake. A corner acrylic box in the sump, or even a small plastic container with a hole in in for the pump intake, will do this.

The deep sand bed will be easier to maintain if it is in a removeable bucket. It is hard to siphon stuff out of a sump at floor level.

I wouldn't grow Xenia or anything else in the skimmer compartment. You want the skimmer are to be clean, you don't want anything to foul the skimmer pump intake.

I would allow more room than is needed for the skimmer. My skimmer barely fits in my sump so it is pain to remove it for cleaning.

I would suggest a modification to the standard baffle design. To most efficiently remove air bubbles with a baffle system, you want the up-flowing water to go fast, and the downflowing water to go slow. A narrow spacing between baffles where the water goes up, and a wide baffle spacing where the water goes down, will accomplish this.