125 gallon and it's half full of slate - too heavy?

I have a 125 gallon and it's half full of slate but I want to fill it to the top.will this be to much weight on the bottom glass.I have a friend that put this huge rock in his tank and the bottom of the tank blew out.

 

It might be to much weight. If you use a dense sheet of foam under the substrate it can protect the tank from pressure points created by the rocks. This would make it safer to try. You would also need to make sure the aquarium is on a good solid even surface so that no pressure points are created because of that. You may already have a piece of foam under the tank but if you don't it should have one there as well.

No guarantees of course but this is the only way I would attempt to do it.

 

My tank is on a DIY stand I build

 

I would be real leery of having that much weight on the glass.

 

I 2nd Dino.