Mytilus 1 year can grow about 1-2 kg, and its weight will be affected by factors such as breeding methods, breeding conditions and management methods. To cultivate mussels, it is necessary to ensure that the water source is sufficient, pollution-free, the transparency of the water area is about 30 cm, and the water surface is required to exceed 6000 square meters. If the area is too small, the water quality will change greatly, which will affect the growth of mussels.

1. How big can mussels grow in a year?

1, mussel 1 How many kilograms long?

Generally speaking, mussels 1 annual energy growth 1-2 kg or so, but due to the influence of culture methods, culture conditions, management methods and other factors, how much kg mussels can grow depends on the actual situation.

2, mussel culture conditions

(1) water source

① The water source is sufficient and pollution-free, the content of toxic substances does not exceed the fishery water quality standard, and the water transparency is 30cm.

② The suitable PH value is 7-8, the suitable water temperature 18-28℃, the suitable water depth 1.5-4m and 2-3m, and the water depth below 1m and above 5m is not suitable for culture.

(3) The water surface should reach more than 6000 square meters. The area is too small, the water quality is unstable and easy to change, which affects the growth of mussels.

(4) It is suggested that mussels should be cultured in waters with a flow rate of less than 0. 1 m. If mussels are cultured in rivers and lakes with running water and other good conditions, they can generally produce 5-8 grams of pearls per year. If cultured in still water, it usually takes about 3 years for each mussel to produce 5-8 grams of pearls.

(2) Lighting

① When the light is sufficient, it can produce thermal effect and provide energy for pearl mussels and their predators.

② When the light is sufficient, the dissolved oxygen content in water will increase, which can promote the movement and heat transfer of water and affect the color of pearls.

(3) Soil quality

The suitable soil in the Pearl River waters is clay, followed by river soil, loess and sandy soil, and there should be a proper amount of silt at the bottom.

(4) Dissolved oxygen

① Summer: The dissolved oxygen content in water should exceed 5 mg/L. ..

② Winter: The dissolved oxygen content in water should exceed 3 mg/L. ..

(5) Material content

① The main component of pearls and pearl mussels is calcium, so the content of inorganic salts in water should be mainly calcium ions, and the calcium content should exceed10 mg/L. If the calcium content is low, quicklime can be sprinkled.

② Algae can't grow without nitrogen, but if the nitrogen content exceeds 2 mg/L, it means that the water body has been seriously polluted, and the growth of mussels will be affected to some extent, and even the survival rate will be reduced. If the nitrogen content is lower than 0. 1 mg/L, it means that the water quality is too thin to meet the proliferation needs of natural bait.

(3) The nitrite content in the water should not be greater than 0. 1mg/L, otherwise the mussel beads will grow slowly and die, which can generally be controlled at 0.01-0.1mg/L. ..

(4) Aquatic vascular plants, shrimps, crabs and other pests should not appear in aquaculture waters to prevent the growth of mussels from being affected.

Second, the culture method of mussels

1, site selection

Generally, it can be cultured in lakes, reservoirs, ponds, ditches, harbors, rivers and other waters (which can meet the breeding conditions of mussels).

2. Breeding methods

(1) Hanging culture: It can be divided into single hanging culture and serial culture. Tandem culture means hanging more than two mussels on the 1 line.

(2) Cage culture: The amount of culture depends on the size of the cage (cage and net clip), and it is necessary to ensure that each mussel can touch the bottom of the cage.

3. Breeding density

In the case of conventional culture, the suitable density of cultured mussels is 800- 1200/mu, and the density of cultured mussels by external oscillation is 600-800/mu. The culture density can also be appropriately adjusted according to the weight and fatness of mussels, water flow speed, water depth and other factors.

Step 4 manage

(1) management of temporary nursing period after operation

① After the operation, the mussel was temporarily placed in fresh water (running water) and allowed to recover 15-30 days. During this period, mussels should not be turned over at will, nor should they be allowed to leave the water surface or open the shell for inspection, so as not to affect their recovery speed and the formation of pearl sacs.

(2) After 30 days, check the remaining mussels, remove the dead mussels, and the remaining mussels can be hoisted and cultured again in the pearl-breeding waters. If the water transparency is less than 30 cm, you can lose weight.

(2) Strengthen water injection and oxygenation.

Mytilus is raised in closed still water, and it is easy to die of hypoxia under the conditions of high temperature, shallow water and low pressure. Therefore, it is necessary to replace and replenish water in time, or maintain the freshness of water quality and sufficient oxygen content to prevent the growth of mussels from being affected under anoxic and anoxic conditions.

(3) Adjust the lifting depth in time.

According to the change of water temperature, water level and season, the hanging depth of pearl mussel is appropriately adjusted. Winter and summer seasons are generally suitable for deep hanging, with a depth of 40-60 cm. Spring and autumn are generally suitable for shallow hanging, with a depth of 15-20cm.

(4) Fertilizing in water

(1) If the water quality is too thin, chemical fertilizer or organic fertilizer can be applied at the same time. You can also pour soybean milk (feed and fertilizer) and apply calcium fertilizer, such as quicklime. If the PH value is low, it can be applied more appropriately, and if the PH value is high, the application amount can be reduced.

② Urea and superphosphate are the main fertilizers, and the appropriate ratio is 1:2 or 1:3, which can be sprayed after mixing with water. The principle of use is to use a small amount for many times, and the dosage is 1kg/ mu.

(3) Organic fertilizer is suitable for bird droppings of chickens and ducks. Quicklime and fermented products should be added before use to ensure full decomposition before use.

(5) Remove accessories

Clean up attached sludge and organisms (such as collembola, freshwater sponge, algae, etc.). ) On the net bags, cages and mussels regularly, wash them every 1 month/time from April to June.

(6) Maintenance of aquaculture facilities

Maintain breeding facilities regularly to prevent unnecessary economic losses.