Butascka,
Your stand is seriously overbuilt. It will hold a tank that weights 3 times as much as the one you will put on this stand. I like to overbuilt too so it's nice to see that I'm not the only one
Some time ago I made an ADA copycat stand and to this day I can't believe how heavy the thing is. But I know it will hold any tank I care to put on it without any bowing.
Here in the US the commercially available stands are build in such a way that you would think they would collapse just by looking at them. But they support the tanks fine. I guess it's physics, but it doesn't make me want to copy their construction.
What are you going to use for doors and sides? MDF and laminate?
--Nikolay