aquarium n : a tank or pool or bowl filled with water for keeping live fish and underwater animals [syn: fish tank, marine museum] [also: aquaria (pl)]
tank for keeping fish
- Croatian: akvarij
- Czech: akvárium
- Finnish: akvaario
- German: Aquarium
- Japanese: 金魚鉢, 養魚鉢, 水槽
- Portuguese: aquário
public place where live fish are exhibited
- Croatian: akvarij
- Finnish: akvaario
- German: Aquarium
- Japanese: 水族館
- Portuguese: aquário
- SAMPA: /a.kwa.RjOm/
An aquarium (plural aquariums or aquaria) is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, and aquatic plants. The term combines the Latin root aqua, meaning water, with the suffix -arium, meaning "a place for relating to".
An aquarist owns or maintains an aquarium, typically constructed of glass or high-strength plastic. Cuboid aquaria are also known as fish tanks or simply tanks, while bowl-shaped aquaria are also known as fish bowls. Size can range from a small glass bowl to immense public aquaria. Specialised equipment maintains appropriate water quality and other characteristics suitable for the aquarium's residents.
History and popularizationIn the Roman Empire, the first fish to be brought indoors was the sea barbel, which was kept under guest beds in small tanks made of marble. Introduction of glass panes around the year 50 allowed Romans to replace one wall of marble tanks, 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, people produced tubs that approached the shape of 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, he soon housed real animals. In 1838, Félix 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, which contained goldfish, eelgrass, and snails, creating one of the first stable aquaria; he published his findings in 1850 in the Chemical Society's journal.
The keeping of fish in an aquarium became a popular hobby and spread quickly. In the United Kingdom, it became popular after ornate aquaria in cast iron frames were featured at the Great Exhibition of 1851. In 1853, the first large public aquarium opened in the London Zoo and came to be known as the Fish House. Philip Henry Gosse was the first person to actually use the word "aquarium", opting for this term (instead of "vivarium") in 1854 in his book The Aquarium: An Unveiling of the Wonders of the Deep Sea. In this book, Gosse primarily discussed saltwater aquaria. In the 1850s, the aquarium became a fad in the United Kingdom. Germans soon rivaled the British in their interest. In 1854, an anonymous author had two articles published about the saltwater aquaria of the United Kingdom: Die Gartenlaube (The Garden House) entitled Der Ocean auf dem Tische (The Ocean on the Table). 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 societies were appearing in Germany. The United States soon followed. 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 of The North American Review of the same year, William Stimson may have owned some of the first functional aquaria, and had 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.
In the Victorian era in the United Kingdom, 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.
Aquaria became more widely popular as houses had an electricity supply after World War I. Electricity allowed artificial lighting as well as aeration, filtration, and heating of the water. Initially, amateur aquarists kept native fish (with the exception of goldfish); the availability of exotic species from overseas further increased the popularity of the aquarium. Jugs made from a variety of materials were used to import fish from overseas, with 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, allowed fish to be successfully imported from distant regions. In 1999 it was estimated that over nine million U.S. households own an aquarium. Figures from the 2005/2006 APPMA National Pet Owners Survey report that Americans own approximately 139 million freshwater fish and 9.6 million saltwater fish. Estimates of the numbers of fish kept in aquaria in Germany suggest at least 36 million. Aquaria come in a variety of shapes such as cuboid, hexagonal, angled to fit in a corner (L-shaped), bow-front (the front side curves outwards). Fish bowls are generally either plastic or glass, either spherical or some other round configuration.
Acrylic aquaria are also available and are the primary competitor with glass. Acrylics are stronger than glass, and much lighter. Acrylic-soluble cements are used to directly fuse acrylic together (as opposed to simply sealing the seam).
A kreisel tank is a circular aquarium designed to hold delicate animals such as jellyfish. These aquariums provide slow, circular water flow with a lack of physical objects. Originally a German design (kreisel means spinning top), the tank has no sharp corners, and keeps the housed animals away from the plumbing. Water moving into the tank gives a gentle flow that keeps the inhabitants suspended, and water leaving the tank is covered by a delicate screen that prevents the inhabitants from getting stuck. There are several types of kreisel tanks. In a true kreisel, a circular tank has a circular, submerged lid. Pseudokreisels have a curved bottom surface and a flat top surface, similar to the shape of either a "U" or a semicircle. It is possible to combine these designs; a circular shaped tank is used without a lid or cover, and the surface of the water acts as the continuation of circular flow.
Aquarium size and volumeAn aquarium can range from a small glass bowl containing less than a litre (34 fl.oz.) of water to immense public aquaria which can house entire ecosystems such as kelp forests. Larger aquaria are typically recommended to hobbyists due to their resistance to rapid fluctuations of temperature and pH, allowing for greater system stability. Aquaria within public aquariums designed for exhibition of large species or environments can be dramatically larger than any home aquarium. The Georgia Aquarium, for example, features an individual aquarium of .
The typical hobbyist aquarium will include a filtration system, an artificial lighting system, and a heater or chiller depending on the inhabitants of the aquarium. Many aquaria incorporate a hood, which prevents evaporation and protects fish from leaving the aquarium (or anything else from entering the aquarium). They also often hold lights.
Aquarium heaters combine a heating element with a thermostat, allowing an aquarist to regulate water temperature at a level above that of the surrounding air, whereas coolers and chillers (refrigeration devices) are for use in cold water aquaria, or anywhere the ambient room temperature is above the desired tank temperature.
The processA well-balanced tank contains organisms that are able to metabolize the waste products of other aquarium residents. The nitrogen waste produced in a tank is metabolized in aquaria by a type of bacteria known as nitrifiers (genus Nitrosomonas). Nitrifying bacteria capture ammonia from the water and metabolize it to produce nitrite. Nitrite is also highly toxic to fish in high concentrations. Another type of bacteria, genus Nitrospira, converts nitrite into nitrate, a less toxic substance to aquarium inhabitants. (Nitrobacter bacteria were previously believed to fill this role, and continue to be found in commercially available products sold as kits to "jump start" the nitrogen cycle in an aquarium. While biologically they could theoretically fill the same niche as Nitrospira, it has recently been found that Nitrobacter are not present in detectable levels in established aquaria, while Nitrospira are plentiful.) This process is known in the aquarium hobby as the nitrogen cycle.
In addition to bacteria, aquatic plants also eliminate nitrogen waste by metabolizing ammonia and nitrate. When plants metabolize nitrogen compounds, they remove nitrogen from the water by using it to build biomass that decays more slowly than ammonia-driven plankton already dissolved in the water.
Maintaining the nitrogen cycle
Although informally called the nitrogen cycle by hobbyists, it is in fact only a portion of a true cycle: nitrogen must be added to the system (usually through food provided to the tank inhabitants), and nitrates accumulate in the water at the end of the process, or become bound in the biomass of plants. This accumulation of nitrates in home aquaria requires the aquarium keeper to remove water that is high in nitrates, or remove plants which have grown from the nitrates.
Aquaria kept by hobbyists often do not have the populations of bacteria needed to detoxify nitrogen waste from tank inhabitants. This problem is most often addressed through two filtration solutions: Activated carbon filters absorb nitrogen compounds and other toxins from the water, while biological filters provide a medium designed for colonization by the desired nitrifying bacteria. Activated carbon and other substances, such as ammonia absorbing resines, will stop working when their pores get full, so these components have to be replaced with fresh stocks constantly.
New aquaria often have problems associated with the nitrogen cycle due to insufficient number of beneficial bacteria, known as "New Tank Syndrome". Therefore new tanks have to be matured before stocking them with fish. There are three basic approaches to this: the fishless cycle the silent cycle and slow growth.
No fish are kept in a tank undergoing a "fishless" cycle. Instead, small amounts of ammonia are added to the tank to feed the bacteria being cultured. During this process, ammonia, nitrite, and nitrate levels are tested to monitor progress. The "silent" cycle is basically nothing more than densely stocking the aquarium with fast-growing aquatic plants and relying on them to consume the nitrogen, allowing the necessary bacterial populations time to develop. According to anecdotal reports of aquarists specializing in planted tanks, the plants can consume nitrogenous waste so efficiently that the spikes in ammonia and nitrite levels normally seen in more traditional cycling methods are greatly reduced, if they are detectable at all. "Slow growth" entails slowly increasing the population of fish over a period of 6 to 8 weeks, giving bacteria colonies time to grow and stabilize with the increase in fish waste.
The largest bacterial populations are found in the filter; efficient filtration is vital. Sometimes, a vigorous cleaning of the filter is enough to seriously disturb the biological balance of an aquarium. Therefore, it is recommended to rinse mechanical filters in an outside bucket of aquarium water to dislodge organic materials that contribute to nitrate problems, while preserving bacteria populations. Another safe practice consists of cleaning only one half of the filter media every time the filter or filters are serviced.
Biological loadingBiological loading is a measure of the burden placed on the aquarium ecosystem by its living inhabitants. High biological loading in an aquarium represents a more complicated tank ecology, which in turn means that equilibrium is easier to perturb. In addition, there are several fundamental constraints on biological loading based on the size of an aquarium. The surface area of water exposed to air limits dissolved oxygen intake by the tank. The capacity of nitrifying bacteria is limited by the physical space they have available to colonize. Physically, only a limited size and number of plants and animals can be fit into an aquarium while still providing room for movement. Simply, all kinds of biology decay, and biological loading refers to that rate of decay in proportion to tank volume.
Calculating aquarium capacityAn aquarium can only support a certain number of fish. Limiting factors include the availability of oxygen in the water and the rate at which the filtration can process waste. Aquarists have developed rules of thumb to estimate the number of fish that can be kept in an aquarium; the examples below are for small freshwater fish, larger freshwater fishes and most marine fishes need much more generous allowances.
- 3 cm of fish length per 4 litres of water (i.e., a 6 cm-long fish would need about 8 litres of water).
- 1 cm of fish length per 30 square centimetres of surface area.
- 1 inch of fish length per gallon of water. To some degree, establishing the maximum loading capacity of an aquarium depends upon slowly adding fish and monitoring water quality over time, essentially a trial and error approach.
Factors affecting capacityThough many conventional methods of calculating the capacity of aquarium are based on volume and pure length of fish, there are other variables. One variable is differences between fish. Smaller fish consume more oxygen per gram of body weight than larger fish. Labyrinth fish, having the capability to breathe atmospheric oxygen, are noted for not needing as much surface area (however, some of these fish are territorial, and may not appreciate crowding). Barbs also require more surface area than tetras of comparable size. Marine aquaria generally require more complex equipment to set up and maintain than freshwater aquaria. Along with fish species, marine aquaria frequently feature a diverse range of invertebrates. Brackish water aquaria combine elements of both marine and freshwater fishkeeping. Fish kept in brackish water aquaria generally come from habitats with varying salinity, such as mangroves and estuaries. Certain subtypes of aquaria also exist within these types, such as the reef aquarium, a type of marine aquarium that houses coral.
Another classification is by temperature range. Many aquarists maintain a tropical aquarium as these fish tend to be more colorful. However, the coldwater aquarium is also popular, which may includes fish such as goldfish. Aquaria may be grouped by their species selection. The community tank is the most common type of aquarium kept today, where several non-aggressive species are housed peacefully together. In these aquaria, the aquarium fish, invertebrates, and plants probably do not originate from the same geographic region, but generally tolerate similar water conditions. Aggressive tanks, in contrast, house a limited number of species that can be aggressive toward other fish, or are able to withstand aggression well. Species or specimen tanks usually only house one fish species, along with plants, perhaps found in the fishes' natural environment and decorations simulating a true ecosystem. This type is useful for fish that simply cannot be housed safely with other fish, such as the electric eel, as an extreme example. Some tanks of this sort are used simply to house adults for breeding.
Ecotype, ecotope, or biotope aquaria is another type based on species selection. In it, an aquarist attempts to simulate a specific ecosystem found in the natural world, bringing together fish, invertebrate species, and plants found only in that ecosystem in a tank with water conditions and decorations designed to simulate their natural environment. These ecotype aquaria might be considered the most sophisticated hobby aquaria; indeed, public aquaria use this approach in their exhibits whenever possible. This approach best simulates the experience of observing an aquarium's inhabitants in the wild. Matching a tank to the environment at the source of fish usually serves as the healthiest possible artificial environment for the tank's occupants.
Most public aquariums feature a number of smaller aquaria, as well those greater in size than could be kept by home aquarists. The largest tanks hold millions of gallons of water and can house large species, including sharks or beluga whales. Dolphinariums are aquaria specifically for housing dolphins. Aquatic and semiaquatic animals, including otters and penguins, may also be kept by public aquariums. Public aquariums may also be included in larger establishments such as a marine mammal park or a marine park.
- Association of Zoos and Aquariums (AZA)
- List of aquarium diseases
- List of brackish aquarium fish species
- List of freshwater aquarium amphibian species
- List of freshwater aquarium fish species
- List of freshwater aquarium invertebrate species
- List of freshwater aquarium plant species
- List of marine aquarium fish species
aquarium in Asturian: Acuariu (recipiente)
aquarium in Bulgarian: Аквариум
aquarium in Catalan: Aquari (recipient)
aquarium in Czech: Akvárium
aquarium in Welsh: Acwariwm
aquarium in Danish: Akvarium
aquarium in German: Aquarium
aquarium in Spanish: Acuario (recipiente)
aquarium in Esperanto: Akvario
aquarium in Persian: آکواریوم
aquarium in French: Aquarium
aquarium in Galician: Acuario (recipiente)
aquarium in Croatian: Akvarij
aquarium in Indonesian: Akuarium
aquarium in Icelandic: Fiskabúr
aquarium in Italian: Acquario (contenitore)
aquarium in Hebrew: אקווריום
aquarium in Latin: Aquarium
aquarium in Lithuanian: Akvariumas
aquarium in Dutch: Aquarium
aquarium in Japanese: 水族館
aquarium in Norwegian: Akvarium
aquarium in Norwegian Nynorsk: Akvarium
aquarium in Occitan (post 1500): Aqüari
aquarium in Uzbek: Akvarium
aquarium in Polish: Akwarium
aquarium in Portuguese: Aquário
aquarium in Romanian: Acvariu
aquarium in Russian: Аквариум
aquarium in Simple English: Aquarium
aquarium in Slovak: Akvárium
aquarium in Finnish: Akvaario
aquarium in Swedish: Akvarium
aquarium in Tamil: நீர்வாழ் உயிரினங்கள் காட்சிச்சாலை
aquarium in Turkish: Akvaryum
aquarium in Ukrainian: Акваріум
aquarium in Chinese: 水族箱