The Goldfish is believed to be not just the most widely kept ornamental fish in the world, but the most popular of all pets. Virtually every aquarist and pondkeeper has kept a Goldfish at one time or another. Although there is documentary evidence of the Goldfish having been kept as a pet in ponds in China as far back as the Sung Dynasty (960-1279 a.d.), there are indications that its history could stretch back to the Western Jin Dynasty (262-315 a.d.), which would make the Goldfish-human association at least 1,700 years old. Over the centuries countless varieties of the Goldfish have been developed in numerous countries. Today there are over 100 officially recognized varieties and an unknown number of “unofficial” ones.
A few of the best-known varieties are shown here. However, as variants are continually combined to select color or fin features, the rate at which new Goldfish varieties become available shows no sign of slowing down. The alternative scientific name given above, Carassius auratus auratus, indicates that the Goldfish was until quite recently regarded as a subspecies of C. auratus, the other one being C. auratus gibelius, the Gibel or Prussian Carp. Today, however, both are regarded as valid species in their own right.
- Carassius auratus auratus
- China and parts of Siberia. However, widely introduced in numerous tropical, subtropical, and temperate regions worldwide.
- Up to around 12in (30cm) for slim-bodied types; round-bodied varieties tend to be considerably smaller, but some types of Orandas, for example, can also grow to substantial sizes.
- Generally peaceful, although some specimens—in particular mature males during the breeding season—can harass other fish. All varieties will eat soft succulent plants and will constantly root around the bottom of the tank.
- All foods accepted; vegetable component important.
- It should be roomy with wide open areas that allow full view of the fish. Robust and/or unpalatable plants should be used, perhaps supplemented with artificial types. Roots should be protected. Water chemistry is not critical but quality must be good. Efficient filtration and aeration are essential. Temperature range: from well below 50°F(10°C) to above 86°F (30°C); higher temperatures should not be maintained on a long-term basis.
- Persistent chasing (driving) by the male—which develops white pimplelike tubercles on its snout and gill covers during the breeding season—will eventually result in the pair (or a shoal) spawning among any fine-leaved vegetation. Goldfish are egg scatterers/eaters, so either they or the eggs should be removed after spawning, which tends to occur at temperatures above 68°F (20°C). Hatching can take up to 1 week, but generally takes less.