Silver carp is a freshwater fish, scientifically known as bighead carp. It mainly grows in river reservoirs, ponds and lakes and other areas. Silver carp is cultured in lakes and medium and large reservoirs, with high yield and low breeding cost, and the cost of silver carp-based culture is about 1.6-2.0 yuan per kilogram of fish.
The unsatisfactory breeding of silver carp generally has the following problems:
1. The trash fish in the reservoir were not removed. Screws, especially wild carp. A large number of trash fish grab most of the bait of silver carp and consume fertilizer, which affects the normal growth of silver carp.
2. There is no timely prevention of parasites.
3. Stocking fingerlings are too small, which will bring two problems: First, the growth cycle is too long to be listed in time, affecting the yield; Second, the survival rate is low. Therefore, the method of large-sized fingerlings should be used to raise small-sized fingerlings.
4. There is no round of catching and putting, no scientific fertilization, and no attention to regulating water quality.
6. Do not pay attention to fertilizer preservation and early spring cultivation of algae in winter.
First, the preparation and stocking of varieties
Fingerling populations correspond to target production. If silver carp is the mainstay, depending on the water conditions, the general yield can reach 220-350 kg. If the planned output is 350 kg / mu, and all are listed in the same year, you need to invest 10%.5-1.40-60 fish, silver carp with more than 8 kg.5-2.8 kg 50 to 60 fish, can be equipped with 10 kg of silver carp.0-1.10-15 kg.
Second, the technical essentials of fertilization and water transfer
1. Apply the base fertilizer. Winter. When the water temperature is low in early spring, organic fertilizer is applied in stages and batches, and organic fertilizer is applied before May. The total amount requires the application of 1500-2000 kg of chicken manure per mu (after decomposition and fermentation).
2. After the air warms up in the early spring, the water body is fertilized for the first time, and algal light can be selected in the early stage. Fertilizer suitable for low temperature use, a small amount of fertilizer in the future. Some fertilizers can also be used: 10 kg of ammonium bicarbonate per acre, or 7 to 8 kg of ammonium chloride sprinkled on the entire pool; urea, 1-2 kg per acre; Phosphate fertilizer can choose 5 to 10 kg of calcium phosphate per mu; Beneficial bacteria can opt for ultra-concentrated spores. EM bacteria, etc. Once every 7-10 days and once for beneficial bacteria 8-12 days. Depending on the water temperature. It depends on the weather.
3. After the water temperature rises in the later stage, ecological fertilizers should be used. For example, the compound algae species, Algae Yiduo, is used every 15-20 days, and the water quality is regulated regularly with excess calcium phosphate and super concentrated spores. When organic fertilizer is sufficiently applied, Streptococcus manure can be applied appropriately. EM regulates bacteria.
III. Parasites
The large water surface is generally deeper silt and the substrate is aging, so there are more pests, if it is not killed, silver carp is easily affected by pests and grows slowly. Especially Qingming. White dew two seasons, pay attention to prevention. Insecticide can use pure Chinese medicine national standard products, must not be used indiscriminately Huayao, there are residues and irritation, easy to cause fish death.
Fourth, fertilize
Winter fish overwintering consumption is large, 11-12 months can be applied in advance of fermented chicken manure, with a certain amount of low temperature fertilizer. In general, low-temperature fertilizer can be applied in early spring and early March, such as algae Yiduo, which is indeed a fertilizer water artifact, which can quickly continue to fertilize water from 0 degrees Celsius to 35 degrees Celsius.
Fifth, the collocation of other varieties
With silver carp as the main species of water, the choice of matching species should not have much conflict with the growth of silver carp. The more successful collocation varieties are yellow ancient fish, white strips, etc., and require removal. Control species such as caiyu and catfish.
6. Precautions
1. The overall control of water and fertilizer to prevent water quality aging and algal phase aging, the water transparency is required to be controlled at about 30cm.
2. Pay attention to testing water quality and water quality regulation. The noon value of water phH can not exceed 9, if it is too high, use spores, EM bacteria, lactic acid bacteria and other strains for adjustment, ammonia nitrogen control at 0.2 ~ 0.3 mg / L, nitrite in 0.05 mg / L. Once the water body is found to be abnormal, it is necessary to adjust the water quality in time so that the water body remains obese for a long time. Live. Tender. Refreshing.
3. Beneficial bacteria must be applied on sunny days. After October, nitrogen fertilizer can be selected ammonium chloride. Ammonium bicarbonate, etc.
4. In the case of no fertilizer after fertilization, different solutions are taken for different reasons. If there are too many zooplankton, local killing methods are adopted. In the early morning, insecticides are killed within half a meter of the pond reservoir, and the amount of cypermethrin + avermectin can be determined according to one-third of the area of water surface. If caused by old water, take EM bacteria. Bacillus. Water transfer solutions such as photosynthetic bacteria.
Seven, two specific requirements
1。 In the middle of the breeding period (May to July), fishing is 1 to 2 times, and the fishing is small. Most of the large silver carp stocked in the stock should be caught in the medium term to reduce the load on the fish per unit of water.
2. The large water surface adopts the high yield model of silver carp, and at the beginning of the year, an aquaculture program must be formulated according to the specific situation of the lake reservoir.