Is it tempered?

[eaglesandfish]

I work in the glass industry. I have never heard of the glasses trick. Unless it is etched with a tempering stamp in the corners, there is no way of telling weather it is tempered or annealed. I have had old glass guys tell me they can hear a difference if the glass is tapped, but i personaly can not tell the difference.

 

[The Zigman]

Most tanks are only tempered on the bottom.

 

[Reefscape]

I work in the glass industry. I have never heard of the glasses trick. Unless it is etched with a tempering stamp in the corners, there is no way of telling weather it is tempered or annealed. I have had old glass guys tell me they can hear a difference if the glass is tapped, but i personaly can not tell the difference.

It does work, when using polarised sun glasses....i can see this when comparing the glass my tank is made out of (not tempered), and the windows on my car (which are tempered)..

 

[Fishieness]

what size is the tank? Can you find a brand anywhere? A tag on the bottom?
it most likely isnt on the side, especially with older tanks.

 

[AquatiCreations]

I know especially on the newer tanks that there is a sticker on the bottom or inside the rim that will tell you "TEMPERED DO NOT DRILL"

 

[j_chicago]

Actually, saw an old forum post somewhere else in the last week. It had a AGA list of all the tank sizes, weight empty and filled, measurements inside and out. It also had which panes are tempered and not. For my old 65G, it said none were tempered.