Foam or no foam?

[BlueAbyss]

If it won't void the warranty on the tank, and the tank is trimmed, I would use a thin sheet of foam that is thin enough that it could not possibly contact the bottom of the tank. Like a 1/4" or so... the underlay idea sounds good.

I was debating this on my tank, and since I've removed the trim from the tank I will be using a sheet of foam under my tank, to cushion the bottom pane of glass. Not because the stand (or rather 'wall unit') I'm using isn't level (which it isn't, I need to shim it), but because I feel that anything between the two flat surfaces, even something as small as a grain of sand, will stress the glass.