How can I tell if glass is tempered?

[TyeAndersonII]

I was wanting to get 75g tank drilled, but I dont know if my glass is tempered. I could not find a tag anywhere on the tank and don't know the manufacter. Is there anyway to tell tempered glass from non-tempered?

[bm5650]

You can try this link. It has several tank sizes and list wich are tempered. I don't know how accurate it is.

http://www.alysta.com/books/fishtank.htm

[partagas]

Sorry, have to be the first to say this. Hit it with a hammer and then look to see how the glass breaks.

Sorry, just had to........:lol:

[TyeAndersonII]

And how should it break if tempered?

[partagas]

Originally posted by TyeAndersonII
And how should it break if tempered?

It won't it will turn like a spider web. Just like a car window.

[TyeAndersonII]

I just made calls to all local glass shops and nobody wants to do the job. One guy thought I was a prank call "why would you want a hole in your fish tank?"he asked. Any other suggestions to get this done?

[partagas]

Call your LFS. They will do it. Don't know what they charge....

[azwhippinboy]

Tempered glass looks different if you look through polarized lenses. On cars it looks like a checkerboard pattern almost. Never tried it with a tank but it may be worth a shot.

-Harley

[jhead67]

Just my .02. But would anybody in there right mind make a tank out of temp glass. If a piece of LR falls on to it the wrong way, what a mess, and I mean an instant mess. Not only the glass but the 75+ gallons of water instantly rushing into the floor.:eek1:

My bet is that it's not temp glass. And yes the LFS should know someone or be able to drill your tank.

[dwall174]

Here's http://www.all-glass.com Web page click on the service then the technical info! note the weight differance the no-tempered 75gal weight is 140lbs where as th 75E that has a tempered bottom is only 98lbs That would be one way (if it's an all-glass tank)

[partagas]

Originally posted by jhead67
Just my .02. But would anybody in there right mind make a tank out of temp glass. If a piece of LR falls on to it the wrong way, what a mess, and I mean an instant mess. Not only the glass but the 75+ gallons of water instantly rushing into the floor.:eek1:

My bet is that it's not temp glass. And yes the LFS should know someone or be able to drill your tank.

I thought Tempered was stronger then reg. Glass.

[partagas]

Just did a search.

STRENGTH
Under wind pressure, tempered glass is approximately four times as strong as annealed glass. It resists breakage by small missiles traveling approximately twice as fast as missiles which break annealed glass. Tempered glass is also able to resist temperature differences (200 ° F - 300 ° F) which would cause annealed glass to crack.
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Annealed Glass 6,000 psi
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Tempered Glass 24,000 psi
Typical Breaking Stress
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[jhead67]

Temp glass might be stronger. But, I've seen both break and temp glass shatters into a million little pieces. And one little tap in the wrong place on any glass could cause it to break. If you break a non temp piece of glass it will either crack or completely break, but the break will be limited, hopefully, to just the area around where the damage occurs. And the tank might still be able to hold some water or just have a slow leak. When temp glass goes the whole pane goes.

Like I say .02.



Info on tempered glass from and old thread on the krib (http://www.thekrib.com/TankHardware/glass.html#7)

[dwall174]

Originally posted by jhead67
[B]Temp glass might be stronger. But, one little tap in the wrong place on any glass could cause it to break. When temp glass goes the whole pane goes.

After seening THIS (http://reefcentral.com/gallery/showphoto.php?photo=2272) I have to agree
:eek2: Talk about having a bad day :eek2:

[dwall174]

oops my mistake I thought I read somewhere that it was was a tempered bottom:eek1: