Surprise! Many of those tropical fish in your aquarium (or that you see in the pet store) don't quite look like their wild cousins. Years of selective breeding has greatly increased the variety of fish available to the casual hobbyist.
Domestic platies, swordtails and other livebearing fish are available in an assortment of blue, red, orange, yellow, white and other colors. Male guppies sport multi-color patterns. Bettas, or Siamese fighting fish, are egglaying fish that have been kept for thousands of years and come in a rainbow's worth of color variations.
Hi-fin platies (and some other species) sport enhanced, fancy larger dorsal (top) fins. Leopard and zebra danios are among the fish types bred to include individuals with long, flowing fins. Some mollies, pearl gouramis and others come in an artificially induced bloated, or balloon variety.
Pink eyed, all white albino Corydoras cats have been popular for many years, and other varieties of albino fish appear occasionally, including Oscars, the China doll goldfish and some tetras. There are even albino underwater African frogs.
Goldfish have probably been kept domestically longer than any other fish species - and diligent Asian hobbyists have produced not only a variety of colors but assorted body shape variations; including double or fantails, chunky bodies, telescope eyes, balloon eyes, upward facing eyes, etc. Their close relatives are koi, a popular outdoor pond fish. Koi have similarly been bred to include a wide variation in colors and patterns; and a longfinned variety known as butterfly koi is available as well.
The fish keeping hobby is not without controversy. Glo-fish are zebra danios in which the genes of certain marine organisms have been added; lending them flourescent red, orange, green and yellow coloration. Some people think this tampering with nature is going too far. Definitely going too far is the practice of injecting certain fish with a hypodermic needle to "tatoo" them with patterns like hearts, tic-tac-toe games, etc. We urge people not to buy these "tatooed" fish as there is a high mortality rate in the process.
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