The goldfish is a large and relatively unknown but very popular cold-water fish! It is the first animal of many children, and often the first fish for beginners with an aquarium. There is a lot of misinformation circulating about it, so let's set the record straight. It is a large fish, 10 to 15 cm minimum, and it lives for a long time, 15 years on average. A jar is not an acceptable habitat for it to live in, it needs space, in a jar or a small aquarium the fish survives as best it can, but it is torture. It does not have 3 seconds of memory, the goldfish can remember information for several months! It has a small brain, but it is not stupid!
The pet goldfish
Goldfish are included in the official list of pets, such as dogs and cats. Indeed goldfish do not exist in the wild, it is a human creation, again like the dog or the cat. It is therefore important to stress the importance of never "releasing" goldfish in a river, the natural biological balance can be unbalanced, moreover, this practice is punished by law.
Be careful not to confuse goldfish with roach (Rutilus rutilus), and carp (Cyprinus carpio), they are of the same family but not the same genus or species. Koi carp can also hybridize with goldfish.
Zoological Name: Carassius auratus
Longevity: on average 10 to 15 years, can reach 20 to 25 years
Size: 15 to 20 cm on average, up to 25-30 cm
Varieties: more than 300
They live a long time, even longer than a cat or a dog! On average their life expectancy is 10 to 15 years, but they can reach 20 to 25 years under good conditions for all varieties. Therefore the "bubble" that we will make life in a jar, and which "holds" 2 to 5 years, it is not a feat, it is a very young dead fish.
Common goldfish can reach at adulthood 15 to 20 cm in aquariums, and 25 to 30 cm in tanks. Asian varieties, such as the Ruskin or Fantail, also reach respectable sizes but grow slower, 15 cm on average in aquariums.
The Cyprinidae family is one of the largest families of fish, there are about 2500 species. Cyprinids are distributed around the world, mainly in Europe, Asia, South Africa, and North America. 95% of Cyprinidae species live in freshwater, the remaining 5% accept brackish water (half-sweet, half-salty). In their natural state, Cyprinidae can live in very cold water but also warm water, in fast currents but also stagnant water.
Selection of varieties of goldfish
In Asian countries, with China in the lead, professional but also amateur breeding has never ceased. Numerous varieties of goldfish have been created through crossbreeding and selection. Some varieties originate from a particular country, such as Ranchu and Ruskin, both of which come from Japan.
In China alone, experts have counted more than 300 different varieties of goldfish, but only about 50 are popular. A variety is defined according to various specific physical characteristics, colors, body, scales, fins...
Much of the mutation of goldfish come from the size of the containers used for their breeding. Indeed, in tanks, in a large volume of water, only the color of the fish can change. With the use of vases, small tanks, and aquariums, the fish have had to adapt to the limited space available to them. This is how their body and fins have been transformed, especially their more compact bodies.
There is no genetic manipulation to obtain this or that variety of goldfish. Only years, and even centuries, of selection by breeders to obtain a specific shape or color, sought after.
In France, it was not until the 1990s that there was a growing interest in Asian forms of goldfish, which were for a long time unavailable or difficult to find in France. England and Germany are the two European countries most advanced in the breeding of quality goldfish. In England, the "Goldfish Society of Great Britain" has existed for many decades, in the U.S.A."The Goldfish Society of America has been organizing breeder competitions for a long time as well.