I'm not an engineer for sure but I can almost promise I could walk up to that example stand (unless it has framing thats unable to be seen from the given photo), mainstream knock-down stands as well as many I've seen built and with one kick collapse them from the side with little effort. Filled or unfilled.
They will work, but if you own your home and are going to build a stand for a large tank why even argue the point of building/overbuilding for safety and peace of mind?
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