If tank is allready drilled then its not tempered?

[M3AN ONE]

Im picking up a tank tomorrow it has black back and is glass. Since back is black cant do the polarized test. My question is since its already drilled for overflows and I want to add another. Is it safe to assume the glass is not tempered.

 

[Midwater]

No. The glass could have been drilled before it was tempered.

 

[BadGaskets]

Exactly. My 120 has 4 holes drilled by the manufacturer AND the sticker indicating that it's tempered

 

[M3AN ONE]

All panels are typical the same so if the clear panels aren’t tempered there should be no reason to expect the back black panel to be right?

 

[Jexnell]

All panels are typical the same so if the clear panels aren’t tempered there should be no reason to expect the back black panel to be right?

Not necessarily, I have seen tanks with tempered big panels and non tempered small side panels.

 

[Midwater]

Generally, as far as I have seen, anything that has been tempered, has the factory temper mark in one of the corners.

 

[jjohnwm]

Well, there's a simple way to be sure, but it's potentially very dramatic and very expensive...

If one panel is black...then obviously they are not all the same. Proceed with caution....

 

[Trouser Bark]

Well, there's a simple way to be sure, but it's potentially very dramatic and very expensive...

That's right! Like Ron Reagan said, "trust but verify"!

Only one way to do that.

I reckon.