Goldfish belong to the Carp, family and are the most common pet fish. They are also one of the first fish breeds to be domesticated. The gold fish was originally derived from the Prussian Carp, a grey fish from Asia.
The golden coloured fish was bred in China about 1 000 years ago. Goldfish have since been bred into many distinct breeds colours, shapes and sizes. During 618–907 AD it was popular in China to keep fish in garden ponds. The fish would be taken out and displayed in glass bowls for special occasions, after which they would be returned to the pond.
Gold fish were introduced to Japan in 1502 and to Portugal and the rest of Europe in 1611. Goldfish became very popular in Southern Europe and were regarded as a symbol of luck. ( I have also heard that Chinese people regard having one red and one black goldfish as lucky)
Goldfish can grow up to about 17 cm and weigh up to 4.5kg, depending on the size of their fish tank or pond, but few goldfish every grow up to the maximum size.
They are freshwater fish and require plenty of oxygen. They are not tropical fish, except for some of the fancier varieties, and should be kept in cold water. In outdoor ponds they fish will be fine even in winter but will be more sluggish.
They produce a lot of waste, which can “poison” the water in their tank. Water should be regularly replaced, with special attention to the water temperature.
It is suggested that there should be once square foot of water per inch of fish, but if a filter/pump is used this can be less. The recommended water temperature for goldfish is 25◦C
The three main varieties according to Western classifications are: Common, Comet and Shubukin, but there are also several fancy varieties.
It is recommend that fish should be fed no more than thrice a day and only as much as they can consume in two minutes.
Gold fish reproduce by laying eggs. Eggs hatch within 48-72 hours, though should be removed from the tank so that they don’t get eaten. Goldfish in ponds are more likely to breed than those in fish tanks.
Many animals’ rights activists oppose the keeping of fish in fish tanks, because of the restrictive nature of the tank environment. In Rome, Italy, it is now prohibited to keep goldfish in bowls. Rome has also banned the giving of goldfish as prizes at carnivals and fairs.
If you want to keep fish, please ensure that you buy a fish tank of adequate size. Please learn about the proper goldfish care, such as feeding, tank- and water requirements and special needs, before you buy goldfish.
These fish have learned that human hands bring food.
It is a common myth that goldfish have a very short memory span of a few seconds but a 1994 experiment at the Palais de la Découverte science museum showed that goldfish could be trained using positive reinforcement. A study at the University of Plymouth in 2003 found that goldfish have a memory span of 3 months at least. It also seems that a goldfish can learn to recognize its human owner, because it associates the human with feeding time.
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