but what if the foam is a thin one, will it help to have a plywood under? Why I suggested this is bcuz I also did that for my new tank (in process). Felt that the foam might not be thick enough for the weight absorption, so placed a plywood underneath. I'm using the off-the-rack wrought iron stand too, which was told that some of this stands are hollow inside. So I thought the centre support bar might not be strong enough esp if it's a marine tank with rocks, sand and for the size used by UWS @ 2.5ft, I'm sure the weight is heavy.
Juz my two-cents :-)