Is It Okay If The Tank Goes Over The Edge Of My Stand?

[Rooster]

Would have to say NEVER use a support smaller than the base, and ALWAYS use polystyrene under all but the smallest tank.... ceiling tiles are a good source, just cut to fit the base of the tank with a sharp blade.
The actual physical support only "needs" to be at the edges, so if it sits on a frame this is fine, but play safe and support the whole base...

This is to ensure that the weight is supported evenly... I have seen the mess cutting simple corners like this makes !
It will only go pear shaped when full.. and they go with a BANG.

 

[Behemoth]

on my 30 gallon take and ends hang over about 1 quarter of an inch on both sides, but for the width i had plenty of space on the front and back of the tank. my tank has been running for about a year and i had no problems with it. but then again my tank rarely hangs over on the ends.