I've been pricing out different ways to build a 480 gallon aquarium. For large projects, plywood is definitely cheapest but it occurred to me that I could buy .75"x36"x86" of plastic, probably pvc, sheeting for a somewhat reasonable price. after you figure in the cost of sealing the plywood, I can't imagine the cost difference is that large. Has anyone tried this? It'd absolutely need to be braced. I'm honestly not worried as much about aesthetics because this is getting set into shelves and the actual pvc wouldn't be visible. My main concern is bowing and whether I'd need supports, in addition to cross bracing, outside the pvc. Has anyone heard of anyone doing this? Obviously, there are also concerns of plastacizers leeching into the water but I've already reached out to a couple manufacturers about that.