Couple of things I would be concened with is
Someone dropping, kicking, falling over the tank & smashing it
& also the fact that most animals do not like being towered over, you may find that when you stand over the tank your Fish will disapear into the Rock work, meaning that everytime you pass or go near the tank your fish will dart away, I think you can overcome the equipment, heat etc. problems but in the end I do think you fish will get stressed with being so low to the ground, (Possibly) in the middle of a room & having shadows pass them constantly