The koi fish’s popularity is increasing daily due to its gorgeous colour patterns, and that they are easy to care for. A koi is a freshwater fish of the cyprinidae family and belongs to the actinopterygii class of animals. Koi fish are descendants of the hardy carp and can be found all around the world. Goldfish and koi fish are distant cousins, as they are both descended from the carp. The word koi comes from Japanese, meaning “carp“.
Koi fish were developed by farmers who noticed the bright colour patches on carp, and bred them to get the beautiful appearance of the species we have today, via selective breeding. Koi fish were originally brought to Japan as a food source.
Koi fish were originally brought to Japan as a food source. Koi fish domestication began around the 19th century in Japan, and they were then kept as pets, instead of food.
There are more than 100 varieties of koi created through breeding, and each variety is classified into 16 groups, according to Zen Nippon Airinkai (a group that leads the breeding and dissemination of koi in Japan).
The most popular koi fish colours include white, cream, blue, black, yellow and red. The koi is a pretty large fish, the size of the fish depending on the environment the koi is raised in; diet, genetics and appropriate water temperatures.
An average koi can grow from between 60-91 cm in length. Koi fish can weigh an average of anything between 13-15 kg. The largest koi fish ever recorded weighed in at a whopping 40.8 kg and was 1.2 meters long.
Koi fish are gentle and will typically not act aggressively towards humans. A koi fish may nibble your finger, which will feel more like pressure than a painful bite. Female koi are more playful and have great personalities and lots of body movement compared to males, according to some studies.
Male and female species of koi are simply called male koi fish and female koi fish. Koi fish enjoy having other koi fish around and are very social.
Koi fish use sounds, vibrations, impulses, motion and various smells to communicate with each other. Koi have been known to bully other types of fish, or non-koi fish, in a pond. Koi fish don’t tolerate drastic or rapid changes in temperature and prefer water temperature that range from 15°C to 25°C. Koi fish are sensitive to the sun and may even get sunburnt if there’s not enough shadow in the pond. In winter times, koi go into a sort of dormancy, using less oxygen and settling to the bottom of the pond where the water is warmer.
Koi are unbelievably powerful swimmers and can swim at a speed of anywhere from 1.6 to 4.8 km per hour.
Koi fish are known as intelligent animals and can recognize the person who regularly feeds them. Koi fish have a row of teeth at the back of their throat known as “Pharyngeal teeth”, which is actually common to other freshwater fish.
These Pharyngeal teeth are used to grind food like shells and insects they find at the bottom of the pond. Koi fish have a typical life span ranging anything from 25 to 60 years. Koi can survive for more than 100 years if they receive proper nutrition, their water is kept clean and filtered, and if kept under good conditions.
The oldest koi fish was a koi named Hanako, who according to history, hailed from Japan and lived to be 226 years old. Koi are omnivorous (consume both plants and animals) and will eat a wide variety of foods including fish food, insects, small bugs, snails, worms, algae, shrimp, rice, peas, apples, bananas, berries, lettuce, and even watermelon.
In the wild, if they’re hungry enough, they will sometimes consume different kinds of fish and their eggs, that are smaller than they are.
Koi fish reproduce through spawning, like most fish, in which the female lays a number of eggs and one or more males fertilize them. Female koi fish can lay anything between 1,000 to 50,000 eggs during one breeding season. Only half of the fertilized eggs typically survive.
A baby koi is known as a fry or fingerling. Koi continue to grow until they reach maturity at around 3 years of age. Koi fish attracts several predators, such as otters, raccoons, snakes, birds of prey, badgers, cats and even dogs.
Koi increase in value on several factors, including the size and the specific breed, by age, length and weight, patterns and colours. The Japanese believe that the koi fish symbolizes strength, courage, wealth, success, good fortune, fertility, determination, perseverance and persistence. Koi fish were brought to the attention of the world after one was given to the Japanese emperor as a gift, in 1914, to grace the imperial palaces’ moat.
The koi fish is a popular tattoo design. Once released into the wild, the koi revert to their natural colouration (that of the common carp) within a few generations. The conservation status of koi fish is currently of Least Concern, although the exact figure of their population is not known.