Do you want a wet/dry or a sump? As a sump with a refugium I don't like that unit. The left side is where the tank water will drain and the protein skimmer should be sitting there too. But, it does not appear to to have enough room for the PS. Also, the second baffle looks like it has an angled top section. I see that producing more bubbles instead of acting as a bubble trap.
Have you looked at Melev's Reef - Sumps & Fuge's
for some designs?