Generally can live to 60-70 years old (according to legend, koi fish is 200 years old). Koi fish has a strong adaptability to the environment, with an adaptation temperature of 2 ~ 30℃. But it can't resist the sharp change of water temperature. When the temperature suddenly drops or rises by 2 ~ 3℃, it is easy to get sick. If the temperature fluctuates by 7 ~ 8℃, the fish will crawl under the water and can't eat. If the temperature suddenly changes greatly; Koi fish will even die immediately. The most suitable water temperature for living in koi fish is 20 ~ 25℃. At this water temperature, koi fish is active in swimming, with a strong appetite, strong physique and bright colors.

Extended data

Koi fish, like goldfish, has no strict requirements on water temperature and water quality. The suitable temperature range is 2℃ ~ 30℃, but it can't resist the sudden change of water temperature and the discomfort of koi fish when the temperature difference suddenly exceeds 2℃ ~ 3℃. The optimum water temperature is 20℃ ~ 25℃. It needs sufficient oxygen and is suitable for living in a slightly alkaline and low hardness water environment.

Koi fish has relatively high requirements for fish tanks. Generally, there are large tanks and cylindrical tanks, both of which have their own advantages and disadvantages in breeding and viewing. Square aquariums are convenient for players to watch from the side and appreciate the overall posture of fish, while tank aquariums generally appreciate the gorgeous colors of koi fish from above. From the point of view of aquaculture, square aquariums can generally be equipped with advanced facilities such as automatic filtration system and water pump, which is more convenient for players to raise, while cylindrical aquariums generally change water regularly to maintain water quality.

Koi fish is round and powerful, colorful, bold and carefree, and has the demeanor of a king. He is the king of ornamental fish. The Japanese regard koi fish as a "divine fish" and a "national fish" precisely because koi fish symbolizes good luck, calm personality, long life and strong endurance, and has the connotation of bullying the weak. The vigorous trunk gives people a sense of strength and courage, even if it is placed on the chopping block, it will not struggle, and it has a fearless demeanor! It can be seen that koi fish is pleasing to the eye and edifies the mood.

References:

Baidu Encyclopedia-koi fish