The King of ornamental Fish-- the Culture technique of Koi

Brocade carp (Brocarded carp), also known as red carp, belongs to the family Cyprinidae in biological taxonomy and belongs to freshwater fish in subtropical and temperate regions. It is a kind of ornamental fish evolved from wild edible carp. It is named for its bright colors and varied markings. With its unique charm, gorgeous body color, chic and graceful swimming posture and vigorous and heroic demeanor, it is more and more popular with fish farmers.

First, the story about koi

The original breed of koi is red carp (Cyprinus carpio). As an ornamental fish, red carp has been very popular in the Ming Dynasty. It is said that koi carp originated from Longzhou koi in Guangxi, Xingguo red carp in Jiangxi and golden carp in Hangzhou, Zhejiang. It was introduced into Japan from China in the early stage, and then it has been artificially selected by the Japanese people for a long time. Now there are more than 100 species. According to literature records, Japanese aristocrats first put koi in ponds for viewing, and it is rare for ordinary people to see them. At the beginning, they were called "red carp", "color carp" and "flower carp", but they were renamed "koi" after World War II. As a friendly emissary of the Chinese and Japanese peoples, Japanese koi settled in China in 1973. Brocade carp originated in China, flourished in Japan, and then returned to China, which can be said to have experienced the process of "export to domestic sales". Nowadays, koi is loved by more and more people for its unique masculine beauty, so that it is known as "king of ornamental fish".

2. Biological characteristics of brocade carp

Koi is a variety of carp, it is gentle, unlike tropical fish to bully the small, to bully the weak, different species, different ages of koi can live in harmony. It has the characteristics of strong vitality, high reproduction rate and good adaptability, and its biological characteristics are basically the same as those of common carp.

1. The suitable water temperature of Koi is 5: 30 ℃, and the optimum temperature is 21: 27 ℃, but it is not adaptable to the sharp change of water temperature. If the temperature rises or falls by more than 3 ℃, the fish will get sick; when the temperature exceeds 10 ℃, the fish will die.

2. Koi grows slowly in strong sunlight, so it is necessary to create a shady environment for it. For example, a shaded Arbor can be built in Tong Kok or feeding area.

3. Koi lives in water by absorbing dissolved oxygen in the gills, sending oxygen to the fish and combining with the absorbed food nutrients to produce energy to maintain life. Therefore, whether there is enough oxygen in the water is the key to raising fish well, and the stocking density should be dilute.

4. Koi is omnivorous. General molluscs, aquatic plants, benthos and microalgae are the delicacies of koi. Koi eats more food in summer and little or no food in winter. Therefore, feeding can be increased or decreased according to different seasons. When the water temperature is above 12 ℃ in spring, the bait can be fed three times a day; when the water temperature is below 12 ℃, only once a day is enough.

5. Koi is an oviparous animal. The male fish matures at 2 years old and the female fish mature at 3 years old. They spawn once a year, and the spawning period is usually from April to June every year. At this time, sexually mature female fish, at 4: 10 in the morning to lay eggs, sticky eggs, a straight diameter of about 2.5 mm, white or light yellow, in vitro fertilization, fertilized eggs had better be picked up and hatched separately. Usually after 4-5 days of hatching, the larvae break out of their shells. Newly hatched larvae can be fed with rotifers and branchlets, and can be fed with crushed egg yolks.

6. Koi is suitable for weak alkaline and low hardness water with PH value of 7.2-7.3. If the hardness of the water is on the high side, there will often be a little congestion on the body surface.

7. The lifespan of koi is very long, usually up to 70 years. The age of koi is the same as that of most fishes, and the number of rings of scales is determined, that is, the lifespan of koi.

3. Variety classification and main characteristics of koi.

After continuous hybridization, improvement and breeding, more than 100 varieties of koi have been bred. Japanese koi are mainly divided into 13 categories according to the distribution of color, markings and scales.

1. Red and white koi: the background color of the body surface is silver and white, inlaid with changing red markings.

2. Dazheng tricolor koi: the background color of the fish is snow white, and scarlet and black markings appear.

3. Write common carp: the fish has a black background with triangular or white or red or yellow markings on it.

4. Zhaohe tricolor koi: the fish has a black background with red and white patterns on it.