Here is a better look at the sump in it's correct orientation. It's all 1/2" acrylic and it's a beast.
From left to right:
Skimmer section, return section, fuge section
The total inside dimensions of the return and skimmer sections are 28" x 17" x 10" high baffles. Total of 20.2 gallons before equipment
The total inside dimensions of the fuge section are 9" x 17" x 16" high to the middle of the overflows. Total of 4.4 gallons before liverock and DSB.
Total estimated water will be 24.6 gallons before equipment, liverock and sand.