So here is the vision for the sump room.
(just in the interest of full disclosure, Skip did the sketchup not me)
The tank will drain from a center overflow into this room and be return fed with an Eheim 1262.
All of that plumbing will be under a false floor (to be installed After the tank is in place actually) going into the sump room.
water will enter the bottom sump on the baffled side.
The "left" side of the sump is the only place in the whole system that will have water levels fluctuate, so this is where the liquid level controller will be installed for top off.
the middle tank above the sump is the frag grow out tank (36x18x12) and above that is the fuge. The fuge drains directly to the frag tank, the frag tank drains to the bottom tank on the other rack. I have been referring to that tank as the "fully isolatable water vessel" which in turn drains back to the sump and the circle is complete as water is returned to the display.
In the corner will sit the skimmer (reeflo orca 250).
There will also be a 55 gallon drum to hold the RO/DI water. A DJ switch will control pumps to add water to the top tank on the second rack which is not plumbed into the system, but can drain into the fully isolatable water vessel.
Yes, this is the water change system.
A valve diverts flow from the frag tanks normal drain flow to the water vessel instead sending water directly to the sump. The water vessel has a drain directly to the sinks drainage system and voila, with a couple of turns I can change 40 gallons of water.
There will also be a chiller plumbed into this system somewhere in the sump room.
Adding a calcium reactor and ozone as well. All functions will be controlled by an RKE (I think, could go with a ACPro, but I think RKE is the move) ---
OK, that's all the news for now.
Off to order some spotlights!