New tank 300 gallon

[lastlight]

I was under the impression that glass thickness, tank height and horizontal span of the glass determines how much bracing you need?

The tank being 48" wide only means he has 2 sides that are 48" long whereas most large tanks are a bit shorter. Far as I understand those 6 foot sides need to be braced like any other 6 foot long tank and the 4 foot sides like any normal 4 foot long tank (all other things like thickness and height being equal).

Maybe I'm missing something though. If you have a 4x2x2 tank, does adding another 4x2x2 onto it to make the tank 4x4x2 require more bracing? I thought the pressure on the seams would be the same.