A Complete Analysis of the Key Points of Salmon Farming Technology
Salmon, also called samon or salman fish, with the scientific name salmon, is mainly distributed in the northern Pacific and the northern regions of Europe, Asia, and America. Salmon has a laterally compressed body, a raised back, sharp teeth, small scales, and a silver-gray color, with orange stripes during the spawning period. Salmon meat is firm and delicious, pink in color and elastic. Norway has the largest output of salmon and is also very famous for it. But the best quality salmon comes from the waters of Alaska in the United States and the waters of England in the United Kingdom. Salmon is one of the fish ingredients more commonly used in Western cuisine.
Farming Conditions
1. Farming pond structure: The farming pond adopts a greenhouse cement floor structure, and the roof can be covered with plastic sheeting. Each cement pond in the greenhouse has an area of 100 sq m and a depth of 1.5-2.0 m. A water inlet is set above the cement pond, a drain is set below, and there is a sewage discharge ditch in the middle of the bottom.
2. Water source: It is best to use deep underground well water. If the iron content in the water is high, a set of tower-type aeration iron removal equipment should also be provided. A water quality analysis should be done before using the water source.
3. Aeration and power generation equipment: one 7-10 kilowatt blower. In addition, prepare one more as a backup. To avoid power outages, a set of generator units should also be prepared.
Preparation Before Stocking
For new cement ponds, they should be soaked in water for 2 months before they can be used for farming. Old cement ponds should be disinfected with bactericidal drugs 10 days before fry and fingerling stocking before use, and the cement pond should be filled with water to a depth of 1 m.
Fry and Fingerling Stocking
Stock 40-50 Pacific salmon of about 30-50 g per cubic meter of water. Generally, after 150-160 days of rearing, the weight per fish can reach 900-1000 g. Fingerlings can be stocked in April in spring.
Feed Feeding
Use pellet feed for domesticated feeding. The crude protein content of the feed is 42-45%%, and the feed particle size is 3.0-6.0 mm. When the water temperature is below 8°C, feed twice a day, once from 8:00-9:00 in the morning and once from 4:00-5:00 in the afternoon. When the water temperature is 8-15°C, feed 3 times a day, with one additional feeding at noon. Each feeding should be about 80% full, that is, until most of the fish swim away. 5. Water temperature regulation: Because Pacific salmon is a cold-water fish, it has relatively strict requirements for water temperature. Its optimal growth water temperature is 13-15°C, while the well water temperature is about 8°C. During the rearing period, two methods can be used to regulate the water temperature. First, when the air temperature is relatively low in early spring and late autumn, cover the greenhouse frame with plastic sheeting to raise the pond water temperature. Second, in summer when the air temperature is relatively high, remove the plastic sheeting and reduce the pond water temperature by increasing the exchange volume of well water. Through the above two methods, the water temperature should be no lower than 5°C at the lowest and no higher than 15°C at the highest, and the water temperature in spring and summer should be maintained at 13-15°C.
Water Quality Adjustment
During the rearing period, keep the pond water fresh, discharge sewage regularly, and change water frequently. The number of water changes and the amount of water changed should be flexibly controlled according to changes in water temperature, water quality, and other conditions. Use a blower to continuously aerate the pond water, and stop supplying air only when feeding bait. Keep the dissolved oxygen in the pond water above 8 mg/L.
Fish Disease Prevention and Control
Adhere to the principle of prevention first. During the farming period, use formalin and Manjing alternately to disinfect the pond water, using the whole-pond splashing method, once every half month. Formalin is used at 20 g per cubic meter of water, and Manjing is used at 0.5 g per cubic meter of water.
Daily Management
1. Assign a dedicated person responsible, patrol the pond all day, regulate the water temperature, adjust the air supply volume well, ensure sufficient dissolved oxygen, and avoid fish gasping at the surface due to lack of oxygen.
2. Frequently check the condition of the fish, and sample and check the growth of the fish once every half month.
3. Keep farming records.