An aquarium is a vivarium usually placed in a place with transparent sides (from glass or high-strength plastic), in which animals and aquatic plants (usually fish, but can also be found invertebrates, amphibians, marine mammals and reptiles) are accommodated, and used for public display. Most aquariums are made of glass panels that are glued using silicone glue. However pure glass is fragile and can only last a short time after cracking. Although in general, the adhesive will release first if the aquarium is overloaded. Aquariums can be made with various types of shapes from cubes, hexagonal prisms, to be adjusted to the shape of the space and table angles. Ball-shaped aquariums or round bowls can be made of plastic or glass.
Although glass aquariums are more susceptible to cracking and heavier than acrylic glass, glass is more scratch resistant. This selection is generally based on artistic considerations. Glass also has thermal insulation that is worse than acrylic, so heat is easier to enter or exit, and glass is more difficult to form than acrylic. Acrylic has a melting point of 160 degrees Celsius, while glass requires a temperature of around 500 degrees Celsius (glass transition temperature) to be formed. Although higher temperatures are needed, abundant availability makes glass cheaper than acrylic. But when building a large aquarium or in large quantities, the price is no longer a consideration but security. Large-size glass shipments have a much higher risk than acrylic. And acrylic is more flexible than glass, so the possibility of cracking is very minimal. Laminated glass is used to combine the advantages of glass and acrylic, which are scratch resistant, flexible, and when cracks occur they are not easily broken.
Hobby aquariums will include filtration systems, artificial lighting systems, and heating or cooling depending on the animals that live in them. Many aquariums also have a cover to reduce evaporation and prevent fish from jumping out or foreign objects into the aquarium.
The combination of mechanical and biological filters is commonly used to convert ammonia from water to nitrate to be used by aquatic plants. Sometimes this filter removes phosphate. The filter media can be home to nitrifying bacteria that carry out the process.
Aquarium heaters combine heating elements with thermostats so that the temperature of the water can be maintained. Likewise with aquarium coolers. The types of thermometers used vary, from alcohol thermometers to digital thermometers. Aquarium owners also use air bubble breakers and fine wave makers to increase the solubility of air in the water.
