All you can do is watch and listen as you fill it up. If it looks or sounds like it's not going to make it, stop and work on external bracing. There is no middle ground here when it comes to tanks like this. It is either absolutely strong enough for the water pressure or it isn't. You don't want something that holds the water but if you added another 50G the walls would blow out. Good luck and video would be great! I cant recall a fail ever getting caught on video here! But really...I hope it does fine with no leaks!