what can i do with 5mm glass??

[tim the toolman]

Originally Posted by sphelps

with the 2' x 2' base I'd say 20" tall with a decent euro brace is fine but probably as big as you'd want to go. It's not really the seams you have to worry about or the tank holding together. If the glass is too thin it will bow/budge causing distortion which can be really annoying.

+1
Euro brace and inside brace the bottom and you should be fine. I have seen a 55g fresh water system of 5mm and it was like 5 years old. Just don't cheap out on the silicone as the sandwich joint between your edges will not be very thick. Also I would run your long sides about 3mm past the edges of your short sides so you can create a double joint and seal the inside corner as well as the outside corner.