Long before Dr. Johnston introduced his first glass aquarium, initial glass production have started in Mesopotamia about seven thousand years ago. Many objects made of glass found with the luxury jewelry made of precious stones.
Glass as building materials began to be used after the flat glass made in bulk in Rome, which is about 30 years BC until the year 345 AD with inflatable technique. Although the flat glass produced in small size and the quality was not good, but the inflatable technique is still used until 17th Century.
In the early 20th century, this technique has a mechanism that can produce glass sheets larger, but a less flat surface, causing distortion of vision. The quality is still quite adequate for the glass window. However, to produce higher quality - for example for a glass mirror two glass surfaces should be polished flat and smooth, so the price is still expensive.
Then in 1959, Pilkington managed to create a process of making glass called the 'float process'. This process can produce excellent quality glass; the surface is flat and free of distortion. The result of this glass is called a Float Glass.
Float Glass
The thickness of float glass ranging from 2 mm to 19 mm - with standard size 305 x 213 cm. While the largest size is 1143 x 305 cm. The varying dimensions give the flexibility to make Aquarium in a large size.
Tempered Glass Aquarium
Tempered glass is a hardened float glass by heating to 700° C, and then suddenly cooled by air spraying evenly on both glass surfaces.
At the same thickness the tempered glass three times stronger than ordinary glass to handle water loads, wind, and collision. "Tempered glass" could not proceed further as cut, polished edges, or make holes. All dimensions and specification must be determined precisely before tempering process.
When you use a tempered glass for aquarium, be careful with the edge or surface damage to the glass because it could be the source of the outbreak of the glass as a whole. When broken tempered glass fragments are dull edge pieces which prevent any serious injuries. Unlike annealed glass breaks into sharp edge pieces.
Laminated Glass Aquarium
Laminated glass is the unification of two pieces (or more) float glass which combined by a layer of Poly Vinylbutyral (PVB) film through the heating and pressing process.
Poly Vinyl film used was very clear, distortion-free, not wrinkled, and did not reduce the glass transparent. PVB film also has a flexible nature and can be very strong blend with glass sheets. Thus, the safety level of laminated glass is very high.
When the aquarium glass breaking then the laminated glass is not going to scatter but it's just cracked. Glass will remain attached to the film and mounted on a frame.
Commonly two sheets of laminated glass used for large-sized aquarium. But for the Aquarium or Glass pond which very large or high usually used three or more sheets of laminated glass.
As well as "tempered glass aquarium" before, the process of cutting and making holes can not be performed on laminated glass. Even if workable it would be very difficult and untidy. So, all sizes and holes must be known exactly before the laminated done.