Fishkeeping
Depictions of the sacred fish of Oxyrhynchus kept in captivity in rectangular temple pools have been found in ancient Egyptian art.
Similarly, 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 fancy goldfish began over 2,000 years ago in Japan and China, respectively.
[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".
The hobby can be broadly divided into three specific disciplines, depending on the type of water the fish originate from: freshwater, brackish, and marine (also called saltwater) fishkeeping.
Livebearing fish such as mollies and guppies are among those most easily raised in captivity, but aquarists also regularly breed many types of cichlid, catfish, characins, cyprinids, and killifish.
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.
Generally speaking, the larger the filtration system depending on its configuration, the more capable it will be of properly maintaining an aquatic environment.
Appropriate handling of these factors, along with a balanced food supply and consideration of biological loading, is a requirement to keep these nutrient cycles in adequate equilibrium.
Aquarists with experience sometimes delve further into trying to find a homeostasis by using external resources to modify the water's alkalinity, hardness, or dissolved content of organics and gases.
Ammonia is produced from fish waste and uneaten food, after this is created it is broken down into nitrites by beneficial bacteria that is present in a properly cycled aquarium.
Additional nitrogen and other nutrients are also made available for root uptake by decomposing organic matter in the substrate as well as the breakdown of mulm.
Activated carbon and other substances, such as ammonia absorbing resins, stop working when their pores fill, so these components have to be replaced with fresh stocks periodically.
Adding too many fish too quickly or failing to allow enough time for the bacteria colony to establish itself in the filter media can lead to ammonia stress.
These include a lack of movement and appetite, inflammation and redness of the gills, fins, and body, and occasionally gasping for air at the water's surface.
Best practice is to flush mechanical filters using compatible water to dislodge organic materials while preserving bacteria populations.
[10] Experienced aquarists warn against mechanically applying these rules because they do not consider other important issues such as growth rate, activity level, social behavior, and such.
[17] Once the tank nears capacity, the best practice is to add the remaining fish over a period of time while monitoring water quality.
The top imported species are the guppy, neon tetra, platy, betta, Chinese algae eater, and goldfish.
In many developing countries, locals survive by collecting specimens for the aquarium trade and continue to introduce new species to the market.
Additionally, some European countries have joined the higher ranks of exporting nations; including Netherlands and Czech Republic.
This has caused the hobby to receive criticism and concern among some animal welfare groups, such as PETA, who accuse aquarists of treating aquarium fish as cheap toys to be replaced when they die.
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.
Blood 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.
[33] 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.
Although GloFish are unharmed by their genetic modifications,[34] 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.
[40][41] Catching fish in the wild can reduce their population sizes, placing them in danger of extinction in collecting areas, as has been observed with the dragonet Synchiropus splendidus.
[45] 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.
[46][49] In January 2011 the Maui County Council passed a measure requiring aquarium fisheries to adopt humane practices for preparing fish for transport to market.
