Soilless Culture Technology of Monopterus Albus in still Water

In the wild, ricefield eel often lives in shallow soil, which is because the soil can provide stable warm conditions and dark living environment. In production, using bamboo tubes, tiles and water plants as fish nests instead of soil can meet the living conditions of Monopterus Albus and carry out soilless culture. Compared with soilless culture, soilless culture of Monopterus Albus has the advantages of low cost of pond construction, convenient observation and management, easy domestication and feeding of compound feed, good control of diseases and insect pests and high benefit. At present, the mode of running water culture is basically adopted in soilless aquaculture, but it is difficult to popularize it in places where water resources are scarce. Soilless culture of Monopterus Albus in still water is easier to popularize than that in running water. Soilless aquaculture in still water has the advantages of saving labor, less investment, quick effect and wide range of adaptation. generally, after a production cycle of 6 to 7 months, the weight of eel can be increased by 3 to 5 times, and the net income of eel pond can reach 100 yuan and 150 yuan per square meter. The key techniques of soilless culture of Monopterus Albus in still water are briefly introduced as follows.

1. Stocking of aquatic plants

The reasonable application of water plants can purify the water quality, reduce the water exchange times of eel ponds to 1-2 times per month, prevent heat and cool down, reduce stress reaction, provide fish nests, control diseases and insect pests and so on. Common water plants are water peanut, water hyacinth, water floating lotus, fine green duckweed and so on. Water plants should be matched reasonably in different seasons, mainly water hyacinth and water lilies in summer, water peanuts and fine green duckweed in spring and autumn, and no water plants in winter to prevent rice field eel from living under water plants. Water plants are usually put in 15 days before the eel is released. Before putting, the aquatic plants should be soaked in 0.01% potassium permanganate solution for half an hour to disinfect, the planting area of aquatic plants should not exceed 2x3 of the whole pond area, and at least 1pm 3 fishing pond area should be vacated to set up the eating table and facilitate the activity of ricefield eel. In the daily management, the excess aquatic plants should be fished out or excessively long aquatic plants should be cut in time. Combined with eel pond disinfection, 0.1 × 0.000001 quicklime was sprinkled on the grass to prevent the infection of aquatic grass pathogen.

2. Fish nest setting

All kinds of pipes, bamboo tubes, tiles, waste tires, water plants, loofah, brown pieces, polyethylene mesh and so on can be used as fish nests. In general, the waste bicycle tires are disinfected with potassium permanganate solution to make eel nests. The tires are placed under the grass, and each small pool can put 5-6 tires. Bamboo tubes can also be used, two bamboo tubes in a row, each pool has 3 to 5 rows, each row spacing of about 0.3 meters. Bricks are padded under each row of bamboo tubes, so that there is a larger space under the bamboo nest, which is convenient for running water to discharge sewage. In order to fix the bamboo nest, it is best to press and put bricks above the entrance of the hole, which also plays a role of shading and concealment.

3. Summer shelter

The still water soilless culture pond of Monopterus Albus is small (15 square meters) and the water level is shallow (15 centimeters and 20 centimeters). The water temperature can easily exceed 30 ℃ in summer, so it is necessary to take shading measures in the pool. Generally, shading nets are set up on the pool, and climbing plants such as grapes, towel gourd and pumpkin are planted by the pool. But be careful to leave 10% or 30% light on the surface of the pool. When the air temperature exceeds 30 ℃, it is necessary to deepen the water level in the pond, reduce the density of ricefield eel, and slowly inject new water (groundwater is used to adjust the water temperature of the fishing pond).

4. Water quality control

4.1 Cross disinfection

The water body was sprinkled in the whole pool with 0.1 × 0.000001 or 1 × 0.000001 quicklime bleaching powder every 10 to 15 days, and cross-used. In the north, the water quality is alkaline and the frequency of using bleach is less; in the south, the water quality is sour, and quicklime can be used more often.

4.2 maintain an appropriate water level

Monopterus Albus should often put its head out of the water to eat and breathe. In order to reduce the physical exertion of the eel, the water level should be shallow. However, the water level is too shallow, the water temperature changes quickly, and the activity space of Monopterus Albus is small, which is not conducive to the growth and development of Monopterus Albus. Therefore, the general water level is 10 to 15 centimeters, which can be deepened to 25 centimeters when the temperature is high. If the water plants grow luxuriantly, you can change the water once a month, and you should replenish the water in time according to the amount of water evaporation.

4.3 maintain biodiversity

Eel ponds should be stocked with field snails, small miscellaneous fish, Loach and so on to remove the residual bait to regulate the water quality. However, it should be noted that these creatures should maintain a reasonable proportion in quantity. Misgurnus anguillicaudatus should not exceed 0.3 kg per square meter eel pond. Loach should be domesticated and fed with compound feed of Monopterus Albus before it can give full play to the role of Loach in eating Monopterus Albus faeces. Stocking toads has a special effect on preventing the plum blossom spot disease peculiar to Monopterus Albus. Generally, only 1 or 2 toads can be put in each small pond. Stocking field snails should not exceed 0.25 kg per square meter of pond. In addition, an appropriate amount of green algae can be cultivated in the pond.

5. Ecological control of diseases and insect pests.

5.1 adjust water temperature

The optimum temperature for the growth of Monopterus Albus is 15: 28 ℃, and the best feeding temperature is 23: 26 ℃. When the water temperature rises, the growth and reproduction of low-temperature-loving pathogens will be inhibited, which will make some diseases occur less, such as water mildew and white spot disease; pay attention to the daily temperature difference of water temperature should not exceed 10 ℃, otherwise printing disease will occur easily. In addition, adjusting the water temperature to the optimum temperature will promote the feeding of ricefield eel and strengthen its physique.