How can I determine between Tempered glass and Nomal gl*****

I had 65G tank.

I want to drill..fhistank.



I ask the a question little ago.


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Anyone know about
"water world aquatics,inc Houston, TX" ??

I have a fishtank from that company.
I tried to call today but the phone number was disconnected.
Is there anyone who knows about that company?

Actually, I want to drill the fishtank which I bought from 'Austin Amazonia'. I believe this fish tank was made from that company.

I am not sure if this tank is the tempered glass or not.
Mine is 65gal and 36x18x24. 5/16" thick.
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