96x24x20 is 200, a good size, but if the wife says 400 and you have the room double down. My tank is close to 400 100x36x26, I wish I had gone 48" wide as a Peninsula tank steals space with a gap on each side. My Tank is LeeMar, who is now Crystal Dynamics, they did a good job on my tank. Precision does very nice work, but I have yet to see a super large size, their edges are mitered and look hot. Glass Cages will be at Rap and they build large tanks. Cad makes some affordable smaller tanks, but I would not advise them for large build. Reefapalooza should net you some good ideas. Any tanks over 300 gallons should be built on metal stands in my opinion and glass is the way to go. If you are ever in Cypress you are welcome to check mine out as well.