Fishkeeping in artificial environments has existed for centuries. In the Roman Empire, the first fish to be brought indoors was the sea barbel, kept in small tanks made of marble under guest beds. With the introduction of glass panes around the year 50, the Romans replaced one wall of the marble tank, improving their view of the fish. In 1369, the Chinese Emperor Hongwu established a porcelain company that produced large porcelain tubs for maintaining goldfish; over time, these tubs were produced more and more like modern fish bowls. Leonhard Baldner, who wrote Vogel-, Fisch- und Tierbuch (Bird, Fish, and Animal Book) in 1666, maintained weather loaches and newts.
In 1836, soon after his invention of the Wardian case, Ward proposed to use his tanks for tropical animals, and in 1841 he did so, though only with aquatic plants and toy fish. However, real animals were soon housed. In 1838, Flix Dujardin noted owning a saltwater aquarium, though he did not use the term. In 1846, Anna Thynne maintained stony corals and seaweed for almost three years, and was credited as the creator of the first balanced marine aquarium in London. At about the same time, Robert Warington experimented with a 13-gallon container, goldfish, eelgrass, and snails, creating one of the first stable aquaria; he published his findings in 1850 in the Chemical Society's journal.
Germans soon rivaled the British in their interest. In 1854, two articles about the saltwater aquaria of Britain were published in Die Gartenlaube (The Garden House) entitled Der Ocean auf dem Tische (The Ocean on the Table) by an anonymous author. However, in 1856, Der See im Glase (The Lake in a Glass) was published, discussing freshwater aquaria, which were much easier to maintain in landlocked areas. During the 1870s, some of the first aquarist socities were appearing in Germany. The United States soon joined. Published in 1858, Henry D. Butler's The Family Aquarium was one of the first books written in the United States solely about the aquarium. According to the July issue The North American Review of the same year, William Stimson may have owned some of the first functional aquaria, as many as seven or eight. The first aquarist society in the United States was founded in New York City in 1893, followed by others. The New York Aquarium Journal first published in October 1876 is considered to be the world's first aquarium magazine.
In the Victorian era of Britain a common design for the home aquarium was a glass front with the other sides made of wood (made watertight with a pitch coating). The bottom would be made of slate and heated from below. More advanced systems soon began to be introduced, along with tanks of glass in metal frames. During the later half of the 19th century, a variety of aquarium designs were explored, such as hanging the aquarium on a wall, mounting it as part of a window, or even combining it with a birdcage.
Aquaria became more widely popular as houses became almost universally electrified after World War I. With electricity great improvements were made in aquarium technology, allowing artificial lighting as well as aeration, filtration, and heating of the water. Initially, amateur aquarists kept native fish (with the exception of goldfish); the entrance of exotic species from overseas also allowed aquaria to become even more popular. Jugs made from a variety of materials were initially used to import fish from overseas, including innovations such as using a bicycle foot pump for aeration. Plastic shipping bags were introduced in the 1950s, making it easier to ship fish. The eventual availability of air freight, which allowed a much wider variety of fish, especially marine, to be successfully imported from distant regions of origin, consequently attracted new hobbyists. In the 1960s, a great breakthrough was reached. Metal frames made marine aquaria almost impossible due to corrosion, but the development of silicone sealant allowed the first all-glass aquaria. The frames remained, however, though purely for aesthetic reasons.
Aquarium keeping is now a popular hobby around the world, with about 60 million enthusiasts worldwide. In the United States, aquarium keeping is the second-most popular hobby after stamp collecting. The number of fish kept in aquaria vary by country. In 1999 it was estimated that over nine million U.S. households own an aquarium. In 2005, it was estimated that 139million freshwater fish and 9million saltwater fish were kept in aquaria in the U.S. Similarly, estimates of the numbers of fish kept in aquaria Germany number at least 36 million. The hobby has the strongest following in Europe, Asia, and North America. In the United States, 40 percent of aquarists maintain two or more tanks at any one time.
