Aquarium (plural, aquariums) is a vivarium of any size having at least one transparent side in which water dwelling plants or animals are kept and displayed. The earliest known aquarists were the Sumerians, who kept fishes in artificial ponds at least 4,500 years ago, records of fish keeping also date from ancient Egypt and Assyria.
The Chinese, who raised carp for food as early as 1000 bce, were probably the first to breed fish with any degree of success. Their selective breeding of ornamental goldfish was later introduced to Japan, where the breeding of ornamental carp was perfected. The ancient Romans, who kept fish for food and entertainment, were the first known marine aquarists; they constructed ponds that were supplied with fresh seawater from the ocean.
Although goldfish were successfully kept in glass vessels in England during the middle 1700s, aquarium keeping did not become well established until the relationship between oxygen, animals, and plants became known a century later.
The aquarium principle was fully developed in 1850 by the chemist Robert Warington, who explained that plants added to water in a container would give off enough oxygen to support animals, so long as their numbers do not grow too large.