# 21inch high aquarium, 6mm glass thickness?



## Marlow (May 29, 2013)

Hello, this is my first post on this forum, I am sorry that it happens to be a question :-(

About two weeks ago I received a used 38 gallon aquarium from my uncle, cleaned with very few scratches or marks in it. First thing I noticed was that the glass looked a bit thin for a 20inch high tank. I measured it, it turns out it is only 6mm thick. It has a tempered glass sticker on the bottom, but no indication of it being tempered glass on the sides.

Am I wrong in thinking that 6mm is too thin for that height? If i'm not, what is the likelihood of it being tempered glass on the sides aswell? I am fairly confused, as it definitely did hold water and fish before before without exploding. I, however, do not want to be the person that it _does_ explode on ..:shock:


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## Marlow (May 29, 2013)

D'oh! Read the sticker more closely, it says all panes are tempered glass.. :-| Well, that's one questioned answered <---<

Is tempered glass stronger than regular glass? I -think- it is, but I'm not sure

Note to self: be extra careful around this tank


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## RSVBiffer (Feb 3, 2014)

The thickness of the glass is not governed by the depth alone but also by the length. There is a safety factor relating to this ratio and 'reputable companies' will not manufacture aquariums below a certain safety factor, commonly 1.5 but often 2.0 or above. Obviously, the higher this safety factor then the 'safer' an aquarium is. As a rough guide (the factor is approx as I don't tend to carry this info in my head ;-))

With 6mm glass the safety factors are 2.2 and 1.8 for a 2' and 3' tank respectively. 6mm glass is not suitable for 4' tank at this depth.
With 9mm glass the factors are 4.0, 3.2 & 3.0 (2', 3' & 4')

6mm glass can be used for a 24" deep tank with a length of 2' and has a safety factor of 2.0.

Tempered glass tends to be 4-5 times stronger than plate glass and therefore the safety factor goes up. Aquarium bottoms are often tempered glass although they can be reinforced in various other ways, double bottoms, bracing etc.


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## Cichlidsrule102 (Mar 29, 2014)

tempered glass mate she'll be right


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