Well since I pretty well had to rebuild the tank, turning this thread into the tank build. (mods could you move it to the correct forum?....please)
The tank is a used one that's made its way around a few times (thanks Ed and Kevin!). Dimensions are 24" wide by 23" tall by 31" depth making it 74 gal. But since guys like to exagerate I'll call it a 75
Finished drilling the new 3/4" bottom for three 1" closed loop returns, a 2" drain for the closed loop inlet and a 1" drain for the sump. I plumbed the closed loop with a 1.5" manifold to try to keep flow even between each of the four returns plus I have a garden hose connection for water changes or as I discovered, emergency drainage. Here's a pic of the new bottom all plumbed. Thanks to Josh (JDigital) for the inspiration on the closed loop.
Here's a view of the sump (a standard 20 gal) and the closed loop pump (Reeflo Dart). I used 2" conduit PVC for the inlet for less restriction than using a regular PVC 90. In the sump I have a Ocean Runner 2500 for the skimmer (Oddysea 160) and return to the display.
A view of the overflow showing the drains and one closed loop return:
For mechanical filtration I like using filter socks so I made this holder to fit onto the closed loop drain. It's made up of (from the bottom) a 2" x 4" ABS adapter, a length of 4" ABS and a 3" x 4" ABS adapter that holds a standard filter sock perfectly. I made it removable in case any fish decide to go "over the wall".
I'm happy to say "the Ark" is now full of water, live rock and the two hawkfish. No casualties from the disaster except some zoos that were eaten in the 120 and a couple of snails on some rock that got cold. More pics once the water clears up.
Francis