Steve, sorrow to hear about this.
If this is your second tank, I’d take a real good look at your stand to make sure it is true. It just seems odd that this would happen a second time. If that stand isn’t true, it could be torquing the tank and causing it to leak.
My suspicion too. Or a mushy floor, that gives when you add the weight.
when it rains it pours...although at least you do have that avatar to at least take some solace...