What is the breeding method of Japanese koi? What about water quality treatment?

Professional answer:

Koi belongs to the family Cyprinidae and is a large and valuable fish that is both ornamental and edible. It has a strong body, bright colors, brilliant markings, and elegant swimming posture. It is known as a "living gem in the water" and implies good luck, joy, prosperity, and happiness. It is also called a "good luck fish" and a "feng shui fish." Koi originated from China. , seed production and improvement in Japan, after years of cross-breeding, a koi with very systematic characteristics has been formed. At present, the domestic and foreign markets are promising, and its breeding technology is as follows.

1. Fish pond construction<. /p>

Choose a place with humus soil, leeward side and sunny side, sufficient water source (preferably spring water rich in mineral elements, which will help increase fish body pigments and make the koi body color more bright and beautiful), and convenient drainage and irrigation. Domestic koi can use the open space in the courtyard or the roof to build a pond. The broodstock pond has an area of ​​30-40 square meters, a pond depth of 1.2 meters-1.5 meters, and a spawning pond of 15-20 square meters. , the water depth is 1 meter - 1.2 meters. The hatching tank is 3-5 meters deep, the water depth is 0.8 meters - 1 meters, the water depth is 0.6 meters - 0.8 meters, the seedling pool is 10-15 square meters, the pool depth is 0.5 meters - 0.6 meters, the water depth is 0.4. meters. The area of ​​the adult fish pond depends on the amount of fish. The larger the area, the better. The depth of the pond is 1.5 meters to 2 meters, and the water depth is 1.5 meters. It is best to build a cement pond with the bottom layer tilted toward the drainage outlet. Remove the alkali before using the new cement pond. After the water is filled, add rice straw or wheat straw, soak it for 15 days, drain the water, and then add new water for use.

2. Propagation and seedling cultivation

Jin. The suitable breeding age for carps is 3-10 years old, with a weight of more than 1.5 kilograms. Choose koi carps with strong physique, crystal clear color, obvious variety characteristics, stable swimming posture, and no disease and injury as broodstock in May every year when the water temperature is stable above 16 degrees Celsius. At the same time, the male and female koi are picked out at a ratio of 1:3 and put into the spawning pool. A sterilized fish nest is placed on top of the spawning group. After spawning, the brood fish are taken out, and the fish nest is left in the pool for incubation. After 5-7 days, the fry will be hatched and then cultivated. After 3-4 days of hatching, the fry will start to float to the surface to feed. At this time, the fry will be taken to the seed pond and used as bait. After 1 week, feed water fleas, red worms, chopped earthworms, etc., and appropriately supplement artificial compound feed. Feed once a day in the morning and afternoon. When the fish grows to more than 2 cm, move it to the adult fish pond. < /p>

3. Feeding and management of adult fish

For large-area cement pond farming, the stocking density is 1 to 3 fish per square meter of water surface, and can be appropriately combined with grass, silver carp, bighead carp, etc. Polyculture. A cement pond can be built directly for viewing in courtyards or hotels. The depth of the pond is preferably 0.6-0.8 meters. The density can be slightly larger and 3-5 fish can be stocked per square meter. Equipped with water spray facilities or circulating micro-flow water conditions, feeding is generally done twice a day. Special color-enhancing materials and breeding materials for ornamental fish can be fed to promote their color and form a perfect body shape. Koi is an omnivorous fish and can be fed. Leftover rice, leftovers, peels, etc. are mixed with 10% animal offal, snails, maggots, earthworms and other animal feeds to make pellets for feeding. The crude protein content of the diet should reach 35% and the crude fat should be maintained at 5-8%. .Adhere to the "four fixed" feeding methods, feeding once in the morning and once in the afternoon. The amount of feeding depends on the water temperature, weather changes and the feeding situation of the fish. It is roughly 2-10% of the total weight of the fish and should be eaten within 10-20 minutes.

Insist on daily inspections and remove remaining bait residues in a timely manner. Change the water every 2-3 days in summer. Change the water every 4-5 days in spring and autumn, and the water change amount is 1/3-1/2 of the original pool. Keep water fresh. In hot and rainy weather, attention should be paid to adding oxygen to prevent pool flooding. In winter, koi can be moved indoors, the water temperature should be kept at 2-10°C, and easily digestible food should be fed appropriately to facilitate overwintering.