12mm tempered or 19mm???

[badar7]

rates of glass in lahore,pakistan (these are lowest rates...whole sale rates)

25mm glass 1200/foot (not confirmed)
19mm glass 500/foot with polish tempered 850/foot
15mm glass 400/foot with polish tempered 700/foot
12mm glass 200/foot with polish tempered 300/foot

1 US dollar=100 pakistan ruppess.......well this is irrelevent as even after doing MBA from a good university,its hard to get a job of 18,000/20,000 pakistani ruppess....so my tank is gona take ma 2 months salary!

 

[David R]

I'm surprised tempered is only slightly more expensive, and that 15mm is double 12mm, but 19mm is only a slight increase over 15mm. I guess part of the jump in price from 12mm to 15mm (as explained to me by my tank maker) is the work involved with cutting it.

As for the strength of toughened/tempered glass, according to this article on out local NZ Fishkeepers website (written by someone very knowledgeable on the subject, most of the glass thickness/safety factor calculators you see on-line are based on his calculations);

Toughened glass is considerably stronger than standard glass. It cannot however be cut. If toughened glass is to be used it must first be cut to size, have its edges finished and then be send away for toughening. The thermal resistance properties of glass are also improved by toughening. Standard 6mm glass will rupture if plunged into water at 21°C if the temperature of the glass is more than 55°C hotter or colder. Toughened glass will rupture at approximately 250°C difference. Toughened glass also has a tensile strength greater than 5 times that of standard glass. Standard glass has a very important advantage when used on aquariums. It tends to fail in a non-spectacular manner, – typically a vertical or diagonal crack. Toughened glass however will fail completely, much like the old style car windscreen (100% shattering).

So the tempered/toughened glass should be strong enough for your build, but if it lets go it's not just going to crack and leak, it will go with a bang....