A detailed guide to practical eel farming techniques, easily mastering the key points of farming

Eel, aliases: white eel, white eel, river eel, Japanese eel, green eel, wind eel, Japanese eel. Eel refers to the general term for species classified under the order Anguilliformes. Also called eel, it is a fish that looks like a long snake-shaped fish and has the basic characteristics of fish. In addition, eels, similar to salmon, have migratory characteristics. Eels belong to the fish family, resemble snakes, but have no scales, and are generally produced in sea areas where saltwater and freshwater meet.

I. Farm conditions

1. Water source: In plain areas, river and lake water are mainly used, while in mountainous areas, stream water and spring water are mainly used. It is best to have groundwater so that deep well water can be extracted for backup. The water consumption of a farm is very large, so the water volume must be sufficient. Generally, about 25 cubic meters of water are needed to raise 1 kilogram of edible eel, so this is used as the basis in design. Suitable water quality is a pH value of 7-8, transparency of more than 20 cm, and no industrial sewage hazard.

2. Power supply: The farm needs a sufficient power supply. Generally, each mu of eel pond needs to be equipped with a 1 kilowatt-powered aerator. An eel farm producing 100 tons of edible eels annually needs at least one 150 kVA transformer, and it must be guaranteed that there will be no power outages year-round.

3. Others: The best soil quality for building a farm is loam. The terrain should be flat, the climate warm. If the warm discharge water of a thermal power plant or hot spring water can be used, the benefits will be even more obvious. In addition, water and land transportation should be convenient so as to transport feed and commercial eels.

II. Design of eel ponds

At present, the common eel ponds in China include two types: open-air still-water type and waste-heat warm flowing-water type. The key points for building the ponds are as follows:

1. Open-air still-water eel pond: Natural water such as river, lake, reservoir and groundwater is used as the water source. The pond construction cost is low and power consumption is low, but the yield is relatively low, generally only 1-2 tons per mu. This is currently the main farming method in China, and the scale of an ordinary eel farm is about 50 mu of water surface. Its eel ponds are graded and farmed according to different specifications of eels, usually divided into four types: first, second, third grade, and edible eel ponds. The pond shape is usually circular or oval, with water inlet and drainage outlets arranged diagonally opposite each other, escape-prevention facilities installed, and a feeding shed set up on the sunny and wind-sheltered side of the pond.

2. Warm flowing-water eel pond: The water temperature is required to be controlled at about 27°C, the most suitable water temperature for eel growth, and flowing-water farming is carried out. Its advantages are fewer diseases, fast growth, and high yield per unit area. It is currently a relatively advanced farming method.

III. Farming techniques

The grow-out of edible eels is the process of raising eel fingerlings weighing about 20 grams to commercial eels weighing 150 grams. Farming methods can be divided into three types: specialized farming, mixed farming and companion farming. The key lies in feed feeding, water quality management and disease prevention and control. Feed feeding requires fixed quality, fixed location, fixed quantity and fixed time. Water quality management should focus on water quality cultivation and control to prevent water deterioration. The normal water quality of an eel pond is tender green, with transparency of about 20 cm and a pH value of 7.5-8.5. At this time, eels feed vigorously and grow rapidly.

1. Fresh feed: Common fresh feeds used in eel farming include tubifex, beauty fleas, cyclops, chironomid larvae, river mussels, yellow clams, snails, small fish, small shrimp and animal offal, etc. The effect of feeding fresh feed is relatively good.

2. Compound feed: Compound feed should be prepared by mixing various raw materials in proportion according to the nutritional requirements of eels at different growth and development stages. Because it has the advantages of complete nutritional components, convenient storage and transportation, and economic benefits, it is an ideal feed for developing eel farming.