Koi is a large ornamental fish, which can even grow to about 1 meter. In order to ensure the health of fish, it is necessary to control the feeding density. Usually, how many fish to raise depends on the size of the fish tank and the size of the fish. It is enough to raise one centimeter of fish with one liter of water. If the density exceeds this density, the water quality will deteriorate faster and the fish will feel uncomfortable.

Koi can adapt to a wide range of temperatures, but the most suitable temperature for their survival is between 20-27 ℃. The higher the temperature, the faster their metabolism. But above 27 ℃, they will cause discomfort. The low temperature is usually not lower than 5 ℃, so in winter, it is best to heat it properly with a heating rod.

Koi fish does not require high water quality, so breeders only need to change water regularly to keep the water quality clean. Usually, water can be changed once every 3-7 days, and the amount of water changed each time is controlled at one third of the total water volume. It should be noted that the water temperature must remain unchanged before and after changing water. If the temperature difference is too large, it will also stimulate fish.

Koi is an omnivorous animal, and breeders need to feed it with animal feed and living bait, so as to ensure balanced nutrition. Usually, it should be fed three times a day, and the amount of food should not be too large each time. It is best to ensure that the fish are eaten in about 5 minutes. In addition, if you overfeed, you should clean it up in time.