What is Tempered Glass?

Tempered glass is a type of safety glass thermally or chemically treated to increase its strength compared with normal glass. A fish tank made of tempered glass will not only be stronger than one made of non-tempered glass – it will be a bit lighter too.

A major disadvantage of tempered glass, however, is that it’s nearly impossible to drill or reshape once tempered. This means that any holes required will need to be drilled before the tempering process which can greatly increase costs. If hit with a blunt force, tempered glass will shatter in to thousands of pieces, while non-tempered glass is more likely to crack.

Many tropical fishing enthusiasts drill through the bottom of their tanks for custom overflows or sump filtration systems, so tempered glass may not be ideal. This is due to the fact that, once tempered, glass cannot be altered, meaning any customisation must be completed prior to tempering. Non-tempered glass is much easier to cut or drill than tempered glass.

Glass tanks also differ from acrylic tanks, another material widely used for tanks and aquariums. As glass is more commonly used it’s a bit more cost effective. Both glass and acrylic tanks are less susceptible to yellowing over long periods of time and have cleaner edges – unlike tempered glass which is more likely to yellow over time and show uneven finishes, warps or ripples.