how do you drill glass

[kgross]

You can check for temper with the polarized lenses......

 

[j.p. harrington]

where do u get polorized lenses though?

 

[kgross]

polarized sun glasses will work, and you can get them lots of places.

kim

 

[j.p. harrington]

how do u check it with them though

 

[Jay180reef]

If you look at most car windows with polarized sunglasses, you will instantly recognize a faint crosshatch/checkerboard pattern in the glass. It's easiest to see on a sunny day. Once you know what to look for, use a bright light and the sunglasses to inspect your tank.