Tempered glass?

[Pharaoh]

true. in north america, most marineland and aqueon tanks have only the bottom glass tempered, and the 1/2" glass used on the sides is not..

their websites list which panels are tempered and which are not.

however, unless your tank is made by one of these two, it doesn't help much.

But some of them wouldn't exactly know for sure. I've spoke with a couple manufacturers, and although they list the general designs on-line, they wouldn't commit to it being 100% like that all the time.