Types of fishkeeping systems
Fishkeepers are often known as "aquarists", since many of them are not solely interested in keeping fish. The hobby can be broadly divided into three specific disciplines according to the type of fish: freshwater, brackish, and marine (also called saltwater) fishkeeping.Freshwater
Freshwater fishkeeping is by far the most popular branch of the hobby, with even small pet stores often selling a variety of freshwater fish, such as goldfish, guppies, and angelfish. While most freshwater aquaria are set up as community tanks containing a variety of peaceful species, single-species breeding aquaria are also popular. Livebearing fish such as mollies and guppies are among the species that are most easily raised in captivity, but aquarists also regularly breed numerous other species, including many types of cichlid, catfish, characin, and killifish.Many fishkeepers create freshwater aquascapes where the focus is on aquatic plants as well as on the fish. These aquariums include the "Dutch Aquarium", in reference to the pioneering work carried out by European aquarists in designing these sorts of tanks. In recent years, one of the most active advocates of the heavily planted aquarium is the Japanese aquarist Takashi Amano.
Garden ponds are in some ways similar to freshwater aquaria, but are usually much larger and exposed to the ambient climatic conditions. In the tropics, tropical fish can be kept in garden ponds, but in the cooler regions temperate zone species such as goldfish, koi, and orfe are kept instead.
[edit] Saltwater
Marine aquaria are generally more difficult to maintain and the livestock is significantly more expensive. As a result this branch tends to attract more experienced fishkeepers. Marine aquaria can be exceedingly beautiful, due to the attractive colors and shapes of the corals and the coral reef fish kept in them. Temperate zone marine fish are not as commonly kept in home aquaria, primarily because they do not thrive at room temperature. Coldwater aquaria must provide cooler temperature via a cool room (such as an unheated basement) or a refrigeration device known as a 'chiller'.Marine aquarists often attempt to recreate a coral reef in their aquaria using large quantities of living rock, porous calcareous rocks encrusted with coralline algae, sponges, worms, and other small marine organisms. Larger corals as well as shrimps, crabs, echinoderms, and mollusks are added later on, once the aquarium has matured, as well as a variety of small fish. Such aquaria are sometimes called reef tanks.
[edit] Brackish water
Brackish water aquaria combine elements of the other types, with salinity that must stay between that of freshwater and seawater. Brackish water fish come from habitats with varying salinity, such as mangroves and estuaries, and do not do well if kept permanently in freshwater. Although brackish water aquaria are not necessarily familiar to inexperienced aquarists, many species prefer brackish water, including some mollies, many gobies, some pufferfish, monos, scats, and virtually all the freshwater soles.[edit] The origins of fishkeeping
Fish have been raised as food in pools and ponds for thousands of years. Brightly colored or tame specimens of fish in these pools have sometimes been valued as pets rather than food. Many other cultures kept fish for both functional and decorative purposes.
Ancient Sumerians were known to keep wild-caught fish in ponds, before preparing them for meals. Depictions of the sacred fish of Oxyrhynchus kept in captivity in rectangular temple pools have been found in ancient Egyptian art.
Similarly, throughout Asia has experienced a long history of stocking rice paddies with freshwater fish suitable for eating, including various types of catfish and cyprinid. Selective breeding of carp into today's popular and completely domesticated koi and goldfish is believed to have begun over 2,000 years ago in Japan and China, respectively. The Chinese brought goldfish indoors during the Song Dynasty to enjoy them in large ceramic vessels.
In Medieval Europe, carp pools were a standard feature of estates and monasteries, providing an alternative to meat on feast days when meat could not be eaten for religious reasons.
Marine fish have been similarly valued for centuries. Wealthy Romans kept lampreys and other fish in salt water pools. Tertullian reports that Asinius Celer paid 8000 sesterces for a particularly fine mullet. Cicero reports that the advocate Quintus Hortensius wept when a favored specimen died, while [1] Rather cynically, he referred to these ancient fishkeepers as the Piscinarii, the "fish-pond owners" or "fish breeders", for example when saying that ...the rich (I mean your friends the fish-breeders) did not disguise their jealousy of me.[2][3][4]
[edit] Aquarium maintenance
Balance is facilitated by larger volumes of water which dilute the effects of a systemic shock. For example, the death of the only fish in a 3 US gallons (11 l) tank causes dramatic changes in the system, while the death of that same fish in a 100 US gallons (380 l) tank with many other fish in it creates only a minor imbalance. For this reason, hobbyists often favor larger tanks when possible, as they require less intensive attention.
A variety of nutrient cycles are important in the aquarium. Dissolved oxygen enters at the surface water-air interface or through the actions of an air pump. Carbon dioxide escapes into the air. The phosphate cycle is an important, although often overlooked, nutrient cycle. Sulfur, iron, and micronutrients enter the system as food and exit as waste. Appropriate handling of the nitrogen cycle, along with an adequately balanced food supply and consideration of biological loading, is usually enough to keep these nutrient cycles in adequate equilibrium.
[edit] Water conditions
The solute content of water is perhaps the most important aspect of water conditions, as total dissolved solids and other constituents can dramatically impact basic water chemistry, and therefore how organisms are able to interact with their environment. Salt content, or salinity, is the most basic classification of water conditions. An aquarium may have freshwater (salinity below 0.5 PPT), simulating a lake or river environment; brackish water (a salt level of 0.5 to 30 PPT), simulating environments lying between fresh and salt, such as estuaries; and salt water or seawater (a salt level of 30 to 40 PPT), simulating an ocean or sea environment. Rarely, even higher salt concentrations are maintained in specialized tanks for raising brine organisms.Several other water characteristics result from dissolved contents of the water, and are important to the proper simulation of natural environments. The pH of the water is a measure of the degree to which it is alkaline or acidic. Saltwater is typically alkaline, while the pH of fresh water varies more. Hardness measures overall dissolved mineral content; hard or soft water may be preferred. Hard water is usually alkaline, while soft water is usually neutral to acidic.[5] Dissolved organic content and dissolved gases content are also important factors.
Home aquarists typically use modified tap water supplied through their local water supply network to fill their tanks. Because of the chlorine used to disinfect drinking water supplies for human consumption, straight tap water cannot be used. In the past, it was possible to "condition" the water by simply letting the water stand for a day or two, which allows the chlorine time to dissipate.[5] However, chloramine is now used more often as it is much stabler and will not leave the water as readily. Additives formulated to remove chlorine or chloramine are often all that is needed to make the water ready for aquarium use. Brackish or saltwater aquaria require the addition of a mixture of salts and other minerals, which are commercially available for this purpose.
More sophisticated aquarists may make other modifications to their base water source to modify the water's alkalinity, hardness, or dissolved content of organics and gases, before adding it to their aquaria. This can be accomplished by a range of different additives, such as sodium bicarbonate to raise pH.[5] Some aquarists will even filter or purify their water prior to adding it to their aquarium. There are two processes used for that: deionization or reverse osmosis. In contrast, public aquaria with large water needs often locate themselves near a natural water source (such as a river, lake, or ocean) in order to have easy access to a large volume of water that does not require much further treatment.
The temperature of the water forms the basis of one of the two most basic aquarium classifications: tropical vs. cold water. Most fish and plant species tolerate only a limited range of water temperatures: Tropical or warm water aquaria, with an average temperature of about 25 °C (77 °F), are much more common, and tropical fish are among the most popular aquarium denizens. Cold water aquaria are those with temperatures below what would be considered tropical; a variety of fish are better suited to this cooler environment. More importantly than the temperature range itself is the consistency in temperature; most organisms are not accustomed to sudden changes in temperatures, which could cause shock and lead to disease.[5] Water temperature can be regulated with a combined thermometer and heater unit (or, more rarely, with a cooling unit).
Water movement can also be important in accurately simulating a natural ecosystem. Aquarists may prefer anything from still water up to swift simulated currents in an aquarium, depending on the conditions best suited for the aquarium's inhabitants. Water movement can be controlled through the use of aeration from air pumps, powerheads, and careful design of internal water flow (such as location of filtration system points of inflow and outflow).
[edit] Nitrogen cycle
[edit] The process
A 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. However, this is only temporary, as the plants release nitrogen back into the water when older leaves die off and decompose.
[edit] 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 requisite 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 specially 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 the "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. More commonly 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.
[edit] Biological loading
[edit] Calculating aquarium capacity
An aquarium can only support a certain number of fish[6]. Limiting factors include the availability of oxygen in the water and the rate at which the filter can process waste. Aquarists have developed a number of rules of thumb to allow them to estimate the number of fishes that can be kept in a given aquarium; the examples below are for small freshwater fish as larger freshwater fish and most marine fishes need much more generous allowances.- 1 inch of fish length per gallon of water.[7]
- 1 inch of fish length per 12 square inches of surface area.[8]
- 3 cm of fish length per 4 liters of water (i.e., a 6 cm-long fish would need about 8 liters of water).[7]
- 1 cm of fish length per 30 square centimeters of surface area.[8]
The most important variance on the above rule is that the actual capacity of the tank, regarding oxygenation, is surface area, not gallons. The reason the ratio appears to work is that tanks tend to have a vaguely related gallons/surface ratio, because they get longer as they get larger, rather than retaining the same overall proportions.
Because of this, tall tanks cannot support as many fish as normal, "rectangular" tanks. One must limit more severely the number of fish in a hexagonal tank, for example. Likewise, a good means of oxygenating the water, for example a power filter, increases the number of fish that a tank can support.
[edit] Factors affecting capacity
Though many conventional methods of calculating the capacity of aquarium is 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.[5]Oxygen exchange at the surface is an important constraint, and thus the surface area of the aquarium. Some aquarists go so far as to say that a deeper aquarium with more volume holds no more fish than a shallower aquarium of the same surface area. The capacity can be improved by surface movement and water circulation such as through aeration, which not only improves oxygen exchange, but also the decomposition of waste materials.[5]
The presence of waste materials presents itself as a variable as well. Decomposition is an oxygen-consuming process, therefore the more decaying matter there is, the less oxygen as well. Oxygen dissolves less readily in warmer water; this is a double-edged sword as warmer temperatures make more active fish, which in turn consume even more oxygen. Stress due to temperature changes is especially obvious in coldwater aquaria where the temperature may swing from low temperatures to high temperatures on hotter days.[5]
[edit] Fishkeeping industry
Worldwide, the fishkeeping hobby is a multi-billion dollar industry. The United States is the largest market, followed by Europe and Japan. In 1994, 10.6% of U.S. households owned ornamental freshwater or saltwater fish, with an average of 8.8 fish per household. In 1993, the retail value of the fish hobby in the United States was $910 million.From 1989 to 1992, almost 79% of all U.S. ornamental fish imports came from Southeast Asia and Japan. Singapore, Thailand, the Philippines, Hong Kong, and Indonesia were the top five exporting nations. South America was the second largest exporting region, accounting for 14% of the total annual value. Colombia, Brazil, and Peru were the major suppliers.
Approximately 201 million fish worth $44.7 million were imported into the United States in 1992. These fish comprised 1,539 different species; 730 freshwater species, and 809 saltwater species. Freshwater fish accounted for approximately 96% of the total volume and 80% of the total import value. Only 32 species had import values over $10,000. All the top species were freshwater and accounted for 58% of the total imported value. The top imported species are the guppy, neon tetra, platy, betta, Chinese algae eater, and goldfish.
Historically, fish and plants for the first modern aquaria were gathered from the wild and transported (usually by ship) to Europea and America. During the early 20th century many species of small colorful tropical fish were exported from Manaus, Brazil; Bangkok, Thailand; Jakarta, Indonesia; the Netherlands Antilles; Kolkata, India; and other tropical countries. Import of wild fish, plants, and invertebrates for aquaria continues today around the world. Many species have not been successfully bred in captivity. In many developing countries, locals survive by collecting specimens for the aquarium trade., and continue to introduce new species to the market.
[edit] Fish breeding
[edit] Animal welfare
A properly maintained aquarium allows fish to socialize with their own species and in many cases breed successfully. This is in marked contrast to the conditions enjoyed by larger animals like cats and dogs, which are often kept alone and neutered in an environment different from what they would experience in the wild. However, fish are often maintained in inadequate conditions. Therefore they live short lives and never breed.Inexperienced aquarists often keep too many fish in one tank, or add fish too quickly into an immature aquarium, killing many of them.This has given the hobby a bad reputation among some animal welfare groups, such as PETA, who accuse aquarists of treating aquarium fish as cheap toys to be replaced when they die.[10]
Goldfish and bettas in particular have often been kept in small bowls or aquaria that are too small for their needs.[11] In some cases fish have been installed in all sorts of inappropriate objects such as the AquaBabies Micro Aquaria, Bubble Gear Bubble Bag, and Betta in a Vase, all of which house live fish in unfiltered and insufficient water.[12][13] The latter is sometimes marketed as a complete ecosystem because a plant is included in the neck of the vase. Some sellers claim the fish eat the plant roots. However, bettas are carnivorous and need live food or pellet foods. They cannot survive on plant roots. Another problem is that the plant sometimes blocks the betta's passage to the water surface. They are labyrinth fish, and need to breathe at the surface to avoid suffocation.
Such products are aimed at people looking for a novelty gift. Aquarists actively condemn them. Similarly, the awarding of goldfish as prizes at funfairs is traditional in many parts of the world, but has been criticized by aquarists and activists as cruel and irresponsible. The United Kingdom outlawed live-animal prizes such as goldfish in 2004.[14]
The use of live prey to feed carnivorous fish such as piranhas also draws criticism.[15]
[edit] Fish modification
Modifying fish to make them more attractive as pets is increasingly controversial. Historically, artificially dyeing fish was common. glassfish in particular were often injected with fluorescent dyes.[16] The major British fishkeeping magazine, Practical Fishkeeping, has been effective in its campaign to remove these fish from the market by educating retailers and aquarists to the cruelty and health risks involved.[17]In 2006, Practical Fishkeeping published an article exposing the techniques for performing cosmetic surgery on aquarium fish, without anaesthesia, as described by Singaporean fishkeeping magazine Fish Love Magazine. The tail is cut off and dye is injected into the body.[18] The piece also included the first documented evidence to demonstrate that parrot cichlids are injected with coloured dye. Hong Kong suppliers were offering a service in which fish could be tattooed with company logos or messages using a dye laser; such fishes have been sold in the UK under the name of Kaleidoscope gourami and Striped parrot cichlid.[19] Some people give their fish body piercings.[15]
Hybrid fish such as flowerhorn cichlids and parrot cichlids are highly controversial. Parrot cichlids in particular have a very unnatural shape that prevents them from swimming properly and makes it difficult for them to engage in normal feeding and social behaviors. The biggest concern with hybrids is that they may be bred with native species, making it difficult for hobbyists to identify and breed particular species. This is especially important to hobbyists who shelter species that are rare or extinct in the wild.[20] Extreme mutations have been selected for by some breeders; some fancy goldfish varieties in particular have features that prevent the fish from swimming, seeing, or feeding properly.
Genetically modified fish such as the GloFish are likely to become increasingly available, particularly in the United States and Asia. Although GloFish are said to be unharmed by their genetic modifications,[21] they remain illegal in many places, including the European Union, though at least some have been smuggled into the EU, most likely from Taiwan, via the Czech Republic.[22]
[edit] Conservation
There are two main sources of fish, either from the wild or by breeding them in captivity. United Nations studies show that more than 90% of freshwater aquarium fish are captive bred, while virtually all marine fish and invertebrates are caught. The few marine species bred in captivity supplement but rarely replace the trade in wild-caught specimens.[23][24] Wild-caught animals provide valuable income for people in regions lacking other high-value exports.[25]Marine fish are typically less resilient during transport than freshwater fish, and relatively large numbers of them die before they reach the aquarist. Although the aquarium trade probably represents a minor threat to coral reefs compared to habitat destruction, fishing for food, and climate change, it is a booming trade and may be a serious problem in specific locations such as the Philippines and Indonesia where most collecting is done.[26][27] Catching fish in the wild can potentially reduce their population sizes, placing them in danger of extinction in the areas where the fish are collected, as has been observed with the dragonet Synchiropus splendidus.[28]
[edit] Collecting
In theory, reef fish should be a good example of a renewable resource that encourages fishermen to maintain the integrity and diversity of the natural habitat: more and better fish can be exported from pristine habitats than those that have been polluted or over-harvested. However, this has not been the case in similar industries such as fur trapping, logging, or fishing that experience the tragedy of the commons. There is good evidence that intensive collecting can result in a decline in fish populations.[citation needed]Fish are caught by net, trap, or cyanide.[29] Collection in the wild has several disadvantages. Collecting expeditions can be lengthy and costly, and are not always successful. Fish can also be injured during collection and/or shipping; mortality rates during shipping are high. Many others are weakened by stress and become diseased.
Other problems include the poisoning of coral reefs and non-target species, the depletion of rare species from their natural habitat, and the degradation of ecosystems from large scale removal of key species. Additionally, destructive fishing techniques concern environmentalists and hobbyists alike. There has been a concerted movement to captive breeding and certification programs for wild-caught fish. Two thirds of American marine aquarists surveyed in 1997 preferred farmed coral, and over 80% think that only sustainably caught or farmed fish should be traded.[citation needed]
[edit] Cyanide
Cyanide, a poison that stuns and immobilizes fish, is more damaging than net or trap capture. It can irreversibly damage or kill the fish intended for capture, as well as other fish or invertebrates that are left behind. It has become in the interest of wholesalers and hobbyists to not purchase fish caught by this method. Some UK-based wholesalers advertise their avoidance of cyanide-caught animals. In the Philippines, overfishing and cyanide caused a drastic decline in aquarium fish.[30] Now, the Philippines have started a movement away from cyanide and towards nets.[31] Cyanide is also often used for collecting freshwater species, especially in muddy water with lots of vegetation, complicating catching small and fast moving fish.[edit] Captive breeding and aquaculture
Since the Siamese fighting fish (Betta splendens) was first successfully bred[citation needed] in France in 1893, captive spawning and brooding techniques used in aquaculture have slowly improved. Captive breeding for aquaria is concentrated in southern Florida, Singapore, Hong Kong, and Bangkok, with smaller industries in Hawaii and Sri Lanka.[citation needed] Captive breeding of marine organisms has been in development since the mid-1990s. Breeding for freshwater species is more advanced than for saltwater species. Currently, only a few captive-bred marine species are in the trade, including clownfish, damselfish, and dwarf angelfish.[31]Aquaculture can help in lessening the impacts on wild stocks, either by using cultivated organisms for sale or by releasing them to replenish wild stocks. Breeding programs help preserve species that have become rare or extinct in the wild, most notably the Lake Victoria cichlids.
Some species have also become important as laboratory animals. Cichlids and poecilids are especially important for studies on learning, mating, and social behavior. Hobbyists also keep and observe many fishes not otherwise studied, and thereby provide valuable ecological and behavioral data.
Captive breeding has reduced prices for hobbyists, but cultured animals remain more expensive. Selective breeding has also led to wider intra-species variation, creating more diverse commercial stocks.[31]
[edit] Invasive species
Serious problems can occur when fish originally kept in ponds or aquaria are released into the wild. While tropical fish do not survive in temperate climates, they can thrive in waters with climatic conditions similar to their native climate. Non-native species that become established are called exotic species. Freshwater examples include various cichlids in Florida, goldfish in temperate waters, and South American suckermouth catfishes in warm waters around the world.[32][33] Invasive species can seriously disrupt their new homes by preying on, or competing with, native species. Many marine fish have also been introduced into non-native waters.[34][edit] References
- ^ The Roman Way, lll - Filling the day (BBC Radio 4, 5 March 2007)
- ^ Cicero, Letters to Atticus (Epistulae ad Atticum) 1.18
- ^ Cicero, Letters to Atticus (Epistulae ad Atticum) 1.19
- ^ Cicero, Letters to Atticus (Epistulae ad Atticum) 1.20
- ^ a b c d e f g h Axelrod, Herbert, R. (1996). Exotic Tropical Fishes. T.F.H. Publications.. ISBN 0-87666-543-1.
- ^ "How many fish can you keep in your tank?". AquaDaily. 2009-01-23. http://aquadaily.com/2009/01/23/how-many-fish-can-you-keep-in-your-tank/. Retrieved 2009-02-26.
- ^ a b Ulrich Baensch, Tropical Aquarium Fish, Tetra, 1983
- ^ a b Peter Scott, The Complete Aquarium, Dorling Kindersley, 1996, ISBN 0-7513-0427-1
- ^ Chris Andrews, Adrian Exell, & Neville Carrington, The Interpet Manual of Fish Health, Salamander Books, 1988, ISBN 0-86101-368-9
- ^ Fish in Tanks: No, Thanks! (People for the Ethical Treatment of Animals, 22 April 2007)
- ^ Aqua-Torture (People for the Ethical Treatment of Animals, 22 April 2007)
- ^ Abuse: Boycott AquaBabies (Freshwater Fish F.A.Q.'s, 22 April 2007)
- ^ Aqua-Torture (People for the Ethical Treatment of Animals, 22 April 2007)
- ^ R.I.P. Prize Goldfish in a Bag (BBC News, 22 April 2007)
- ^ a b Uproar at fish cruelty on YouTube (Practical Fishkeeping, 17 May 2007)
- ^ Monks, Neale: Crystal clear: keeping glassfish. Practical Fishkeeping, February 2006
- ^ Why it's cruel to dye (Practical Fishkeeping, 22 April 2007)
- ^ Magazine publishes guide to cosmetic fish surgery (Practical Fishkeeping, 22 April 2007)
- ^ Company offers custom fish tattoos with laser (Practical Fishkeeping, 22 April 2007)
- ^ flowerhorns & other hybrids (Sydney’s Cichlid Page, 22 April 2007)
- ^ GloFish Fluorescent Fish Care (GloFish, 22 April 2007)
- ^ British aquarist bred illegal GM fish at home (Practical Fishkeeping, 22 April 2007)
- ^ [1]
- ^ [2]
- ^ [3]
- ^ [4]
- ^ [5]
- ^ [6]
- ^ Baldwin CC, Collette BB, Parenti LR, Smith DG and Springer VG (1996). "Collecting fishes.". In: MA Lang, CC Baldwin (Eds.) The Diving for Science…1996, "Methods and Techniques of Underwater Research" Proceedings of the American Academy of Underwater Sciences (Sixteenth annual Scientific Diving Symposium). http://archive.rubicon-foundation.org/4678. Retrieved 2008-06-15.
- ^ [7]
- ^ a b c Dakin, Nick (1992). The Macmillan book of the Marine Aquarium. New York: Macmillan Publishing Company. ISBN 0-02-897108-6.
- ^ Bunkley-Williams L, Williams EH Jr., Lilystrom CG, Corujo-Flores I, Zerbi AJ, Aliaume C and TN Churchill. (1994). The South American Sailfin Armored Catfish, Liposarcus multiradiatus (Hancock), a New Exotic Established in Puerto Rican Fresh Waters. Caribbean Journal of Science. http://www.uprm.edu/publications/cjs/VOL30/P090-094.PDF.
- ^ United States Geological Survey.. "NAS - Species FactSheet Astronotus ocellatus (Agassiz 1831)". United States Government. http://nas.er.usgs.gov/queries/FactSheet.asp?speciesID=436. Retrieved 2007-03-17.
- ^ Marine Ecology Progress Series 266:239
[edit] External links
- http://search.dmoz.org/cgi-bin/search?search=Fishkeeping
- The Aquarium Wiki Encyclopaedia - The Nitrogen Cycle.
- The Aquarium Wiki Encyclopaedia - Bacteria seeding Bottles that work
[edit] Further reading
- Advanced Marine Aquarium Techniques, by Jay Hemdal
- Aquarium Atlas, vol. 1, by Hans A. Baensch and Rudiger Riehl ISBN 1-890087-12-2
- Brackish Water Fishes, by Frank Schäfer ISBN 3-936027-82-X
- The Conscientious Marine Aquarist, by Robert Fenner (2001) ISBN 1-890087-02-5
- Chapman, F.; Sharon A. Fitz-Coy, Eric M. Thunberg, and Charles M. Adams (March 1997). "United States of America Trade in Ornamental Fish". Journal of the World Aquaculture Society 28 (1): 1–10. doi:10.1111/j.1749-7345.1997.tb00955.x.
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