An observation for you that you may very well never have to worry about but i'll point it out anyway because you never know what will happen in the future. From previous posts / photos it is obvious you are a cannister guy and your stands are perfect to hide cannisters in. However, should you decide in the future, for whatever reason, to go down the sump route, you will encounter a pretty basic problem. That is you wont be able to fit a resonably sized sump in, meaning you will have to butcher your stand to do it or make a fresh one.
I am a sump guy and when i built my current stand i didn't think it through. At the moment i cant get my sump out so if i decide to change it in the future i'm in a real pickle. Any future stand I ever make will have a top skirt of 2x8's or even 2x10s to support the length of the tank. The centre support will still be there but only for door purposes and more importantly, it will be REMOVABLE! I will be able to replace sumps easily and not worry about the tank not being supported.
Like I said this may never apply to you but if someone reads it who is into sumps, and is thinking of building a stand, then it might give them something to think about.