Hi tim. Do you still have this tank? Was just browsing the forums and saw your thread. Im setting up my 6th tank which is a 72 bowfront. I am also building a 20l sump lol. Interested in seeing how your sump is set up. Here is s pic of the stand i just finished.
I think I would have over all made it 3 compartments rather than 4. The baffles higher and widened the drain side to accommodate more live rock. But over all still happy with the set up. I modified the return with the egg crate so I could raise the water level and not have the cuprela (sp) get sucked in to the return.