Originally Posted by Wasserpest
I imagine that non-tempered glass will break just as quick.
I'm only quoting the glass fabricators I've spoken to recently. But when we are talking about 1/2" glass, it may crack, and crack badly, you are just going to get water spraying out. Rapidly.
But when tempered glass goes, it explodes
. It becomes not there
. Because it instantly turned into 10 thousand little unconnected pieces.
IMO that's not the same thing.
Your mention of your tank, with a tempered bottom and normal sides is a case in point. (BTW - that appears to be a very typical configuration. The bottom where so much pressure is, but with little chance of serious impact, is often tempered. It's why I'm building my own tank - you can't drill bulkhead holes in that all too common tank configuration)
The tempering allow manufacturers to lower cost - high pressures are there, but the cost of tempering is lower than upgrading the bottom to a thicker glass. And for the same reasons, tempering the sides would lower the production cost even further - stronger and thinner (cheaper) glass on the sides!
But they don't do this. Why? I can only assume that because the risk of catastrophic failure from impact is so high, when you temper the sides too.