It doesn't have to be, just so long as the tank fits on the stand and it looks ok. I've seen the Tetra Aqua Art 60 litre stand and it has a door on which is something I would prefer so I can put everything inside and the colours fit in with the room decor it's going in.
The approx measurements of the tank are 600mm wide and 360mm depth. But if you have something that it would fit on then I'd be interested because I have to get the tank out of the room it's currently in, too much sun.