1 m deep fish pond, what fish is grass carp and silver carp mixed together?
The most common type. It is characterized by wide sources of feed and fertilizer, low cost, high yield and good economic benefits. The stocking specifications of grass carp are divided into 10g, 50g and 150g ~ 500g, and the stocking specifications of silver carp are summer flowers, 50g and 200 ~ 350g, which account for about 45% and 30% of the total stocking amount (about 150kg), respectively, and are matched with bighead carp, bighead carp and silver carp. In high-yield areas, the net yield per hectare can reach about 1 1250 kg. Among them, grass carp and silver carp each account for 30%. The market specification of grass carp is 1.5 ~ 2kg, and silver carp is about 600g g. There are also a considerable number of 150 ~ 500g large fish species.
Grass carp, bighead carp and shad are the main polyculture types.
Commonly used types in the Pearl River Delta. The local water temperature is high, the growing period is long, and the water quality is rich. It can be stocked many times a year, especially bighead carp. There are also silver carp and wild bream. Appropriate amount of bream and eel can be mixed to increase income. The stocking specifications of grass carp are 15g and 350g, and the stocking weight accounts for 35% ~ 40% (about 280kg) of the total stocking amount. The stocking specifications of bighead carp are 300-500g, and the stocking specifications of shad are15-25g and 50g, accounting for 27% and 19% of the total stocking respectively. Grass carp are stocked in 2 batches every year, and bighead carp are stocked in 4 ~ 6 batches every year. The net yield per hectare in high-yield areas can reach about12750kg. The market specification of grass carp and bighead carp is 1 kg. The shad is about150g, and a considerable number of large grass carp and shad species can be produced next year.
The polyculture type is mainly composed of silver carp and bighead carp.
A type widely used in China for a long time. Among them, the stocking amount of silver carp and bighead carp accounts for about 60% of the total stocking amount (about 135 kg), and the proportion of silver carp and bighead carp is about 3 ~ 5: 1. Meanwhile, grass carp, carp, crucian carp, tilapia and bighead carp are mixed together. The market specifications of silver carp and bighead carp are over 500 grams, and the net yield per hectare can reach about 7500 kilograms.
Carp polyculture type
Main types in Northeast China, North China and Northwest China. One is that the stocking specification is 50 ~ 100g, and the stocking amount of carp accounts for 50% ~ 65% of the total stocking amount (about 100kg). Meanwhile, grass carp, silver carp and bighead carp are mixed. The market specification of carp is about 500 grams, and the net yield of high-yield ponds can reach 7500 ~ 8250 kilograms per hectare, with carp accounting for 50% ~ 60%. The other is that the stocking amount of carp accounts for 85% ~ 90% of the total weight (about 190 kg). The net yield per hectare can reach 1.5 thousand kg, with carp accounting for about 85% and the market specification of about 500 grams.
Fertilization for fish culture in fish ponds (1)
Fertilization in ponds is mainly used to breed natural bait for plankton, algae, benthos and other fish. Fertilization in ponds can be divided into two methods: base fertilizer and topdressing.
(1) Apply base fertilizer
Organic fertilizers, such as manure, green manure, manure, etc., are generally used as base fertilizers, and should be applied as soon as possible after the pond is drained in winter, so that the pond water can be fertilized as soon as possible after the fish are released by water injection, and natural bait can be propagated for the fish to eat. Fertilization method: fertilizer can be applied to the bottom of the pool or the edge of the stagnant water area, exposed to the sun for a few days, properly decomposed and mineralized, turned over, dried for a few days and then injected with water. The amount of base fertilizer is large, and it should be applied at one time. According to the fatness of the pond, the type and concentration of fertilizer vary from several hundred kilograms to more than one thousand kilograms per mu. Sometimes the base fertilizer is applied after water injection, and its function is mainly to fertilize water rather than sediment. Fertilizers are piled up in coastal or shallow water areas and turned once every few days, so that the fertilizers gradually decompose and spread in the water. Fertilization ponds and ponds that have been raising fish for many years have more silt at the bottom and generally do not apply base fertilizer.
(2) Topdressing
In the process of fish farming, in order to continuously replenish nutrients in water and make natural bait organisms multiply in large quantities, topdressing is needed, and the amount of one-time fertilization should not be too much (especially in summer) to prevent the head from floating due to lack of oxygen. The number and frequency of fertilization vary with water temperature, weather and species of cultured fish. When the water temperature is high, the number of fertilization is Qin Ying, while when the water temperature is low, it is the opposite. So summer and autumn need a little more diligent application than late spring and autumn. Fertilization can be normal in sunny days, and little or no fertilization is needed in rainy days or sultry days with thunderstorms. The amount of organic fertilizer varies from 50-200 kg per mu at a time (due to different types of fertilizers), and the pool water is maintained. Fat, alive, tender and cool? Suitable. Using inorganic fertilizer as topdressing in ponds can get quick results, but the fertilizer effect time is not long. Generally, the ratio of nitrogen: phosphorus: potassium = 2: 2: 1 or nitrogen: phosphorus = 1: 1 is better, and the fertilization time should be in summer and autumn 10: 00-65438. Ponds that are regularly fertilized must be replenished with fresh water regularly to avoid excessive accumulation of organic fertilizers and metabolic wastes of various organisms in the excessive fertilization, with low oxygen content and poor plankton composition, which will affect the growth of fish.
(2) Feeding
Feeding bait is superior to fertilization in promoting fish growth and increasing yield, so we should try our best to improve the quantity and quality of bait and improve feeding technology in fish farming to obtain high yield.
(1), feed can be divided into animal feed, plant feed and compound feed. The compound feed has more comprehensive nutrition and better feeding effect for fish.
(2) Feeding technology. The basic requirements of feeding are uniform, sufficient and good. Don't let the fish be full and hungry. Try to start eating early and stop eating at night. Can't be intermittent, otherwise: one day without eating, three days is not long? It is easy to get sick and waste feed.
What is the feeding method? Four look? 、? Four decisions? The principle of:
? Four look? Depending on the season, after the fish start eating in spring, with the increase of water temperature, the fish's food intake increases and the amount of bait gradually increases. 6? September is the season with the highest bait consumption. After 10 months, with the decrease of water temperature, the bait also decreased accordingly. Second, the weather, climate change, sultry weather and continuous rain are not suitable for feeding. Third, look at the water quality. When the water quality deteriorates, even in danger of flooding, the feeding should be suspended until new water is injected to adjust the water quality. Fourth, look at the fish's eating and activities, which is the direct basis for determining and adjusting the amount of bait. If all the bait on the bait table is ingested and the fish moves normally, the amount of bait can be increased appropriately. On the contrary, the amount of bait is reduced.
? Four decisions? Feeding is a specific requirement for feeding methods. First, quality judgment, the compound feed requires high crude protein content and easy digestion; Grass should be tender, rootless and muddy, and fish like to eat it. The second is quantitative, the daily feeding amount should not be too much or too little, and it is necessary to eat at the specified time to avoid affecting digestion, absorption and growth when the fish are full and hungry. Green feed should be eaten before dawn, and the daily food intake generally accounts for about 30% of the fish weight; Generally, it is advisable to finish the compound feed within two hours. Third, the green feed should be fed around 9: 00 am, so that the fish can eat in the pool with high dissolved oxygen and improve the utilization rate of bait. According to the water temperature and season, the feeding times of compound feed should be appropriately increased to improve the digestibility of bait. Feeding compound feed 3? Feed every day in April 1? Twice, three times a day in May, 6? Feed it four times a day in September and three times a day in June. 5438+1October,165438+1October. Twice. Fourthly, locating the fixed feeding place is helpful to improve the utilization rate of bait, understand the feeding situation of fish and disinfect the feeding place. Fish are prone to conditioned reflex to specific stimuli. Therefore, when feeding, give specific stimulation (such as sound) to make the fish concentrate near the feeding field before feeding, which can prevent the loss of bait.
(3) blackening the round block wheel
Fishing in rotation is to stop fishing in stages and replenish fish species appropriately, that is? Let's fish in stages, catch the big ones, keep the small ones and make up the small ones. . This production mode can improve the utilization rate of water and bait, which is beneficial to the growth of fish, the balanced listing of fish and the capital turnover. It is a good production mode and the most common application in pond culture.
1, conditions for grabbing and releasing wheels
(1), at the beginning of the year, a sufficient number of large fish species were released, and they reached the market specifications in the middle stage of culture, and then they were fished out of the pond in turn.
(2) All kinds of fish species are complete in specifications and sufficient in quantity, with one row, which meets the requirements of round fishing and round release, and the fish species of the same specifications are even in size.
(3) The gap between individuals of the same species and different specifications should be large, otherwise the growth difference between them is not obvious, which makes it difficult to catch and release in turn.
(4) The bait and fertilizer are sufficient and properly managed, otherwise, in the rotation fishing season, because the fish species grow slowly and have not reached the market specifications, the production will be in a passive situation.
(5) Transform the fishing net from a small net of 1cm to a large net of 4cm. When fishing and pulling the net in turn, only a few fish are left in the net. This is convenient to operate and has high production efficiency.
(6) Skilled, meticulous and correct fishing techniques.
Fish pond knowledge: a fish species is put in;
Cleaning and disinfection before putting fish into a fish pond can be carried out according to the requirements of the fish pond.
1, source of fish species. It should be mainly cultivated by oneself or purchased nearby. It is best to cultivate and feed by oneself, so as to avoid long-distance transportation that harms fish species and brings back germs, leading to illness and death. Therefore, large fishing grounds need to have their own fish base. For example, the mandarin fish culture in Dongjiang Reservoir reached hundreds of cages at the peak, but after that, hundreds of cages of mandarin fish were all destroyed because of the virus brought back by introduction. Now there are basically no mandarin fish in Dongjiang Reservoir.
2, stocking varieties. At present, the traditional stocking varieties are: four major fish, silver carp, carp, bream and so on. In the future, it is necessary to gradually expand the stocking ratio of famous varieties such as Pelteobagrus fulvidraco, Siniperca chuatsi, sturgeon, tilapia, Xiangyun crucian carp and red herring. , highlighting its own characteristics and improving breeding efficiency.
3. Fish species specifications.
For large-scale stocking, the stocking size of grass, silver carp, bighead carp and fingerling is preferably above 5 inches. Less fish species, low survival rate and small food intake affect the yield. Fish ponds that do not implement rotation fishing and rotation release have the same fish species specifications and are convenient for growth; For fish ponds that implement rotation fishing and rotation release, the requirements for stocking fish species are large and small, commonly known as release? Stair fish? Only in this way can we give full play to the potential of increasing production by wheel capture and wheel release.
4. Physical requirements.
Free-range fish species require high quality, healthy shape, the best fish, intact scales and fins, and no parasites and diseases on the body surface. Sick fish cannot be cheap.
5. lead time.
Early stocking is one of the measures for high yield, and the price of sowing in winter is lower than that in spring. After fish come out of the pond in winter, the pond is cleaned and disinfected, and generally stocked in sunny days around the Spring Festival. Because of the low temperature in this period, the fish's activity ability is weak and the scales are tight, so it is not easy to get hurt when fishing and stocking. At the same time, early stocking and early feeding are beneficial to growth.
6, polyculture and reasonable density.
Mixed culture and reasonable close culture of various fish species in fish ponds are important measures to make full use of water bodies, make rational use of feed, give play to production potential and increase fish yield. Polyculture is based on the feeding habits and living habits of various fishes. According to their living habits, fish can be divided into three kinds: pelagic fish (silver carp and bighead carp), pelagic fish (grass carp) and bottom fish (carp and crucian carp). In terms of feeding habits, it can be divided into fat fish (silver carp eats phytoplankton and bighead carp eats zooplankton), herbivorous fish (grass carp and bream prefer clear water), omnivorous fish (carp, crucian carp and tilapia) and carnivorous fish (mandarin fish, yellow catfish and catfish). Make use of their mutual advantages, avoid contradictions and give full play to the potential of water and bait. Reasonable stocking density is based on multi-species polyculture.
Generally speaking, the fat pond should be dominated by silver carp, with silver carp 65,438+020-65,438+050, bighead carp 25-30, grass carp 65,438+000-65,438+020 and carp 65,438 per mu.
Grass carp are mainly raised in the thin pond, with 150 grass carp, 100 silver carp, 50 anchovies and 20 carp per mu.
Intensive ponds and fish ponds raised with compound feed should increase the proportion of main fish farming. In a word, stocking density should be adjusted according to pond conditions, source of fertilizer bait, feeding management level and fish species specifications.
2. Feeding management
? Three points for support and seven points for management? Feed management is the fundamental guarantee for stable and high yield of adult fish.
1, a variety of ways to solve fish feed.
(1) Planting green fodder extensively: Make full use of all open spaces in dry land, houses, ponds and ridges, plant green fodder, and expand the sources of green fodder.
⑵ Raise more livestock and poultry: raise pigs with chicken manure, fish with pig and duck manure, fertilize fields with pond mud, grow vegetables and grass, raise ducks in water, raise chickens in pigsty, and establish an ecological fishery model.
⑶ Fish culture with compound feed to maximize the benefits of water body.
2, the implementation of round catch and release.
Releasing fish by rotation is an advanced fish culture measure created by the masses. Its main advantage is to keep the reasonable density of fish in the pond throughout the feeding period. It is beneficial to the growth of fish and the full play of pond production potential.
Generally, there are two types of wheel grabbing and wheel releasing:
(1) Release the fish at one time, catch them in batches, catch the big ones and keep the small ones. All kinds and specifications of fish will be released at one time, and some fish will be caught in batches after reaching the market specifications.
(2) Stocking in batches, fishing in batches, and raising small fish with big fish, that is, adding some fish species immediately after catching some fish that meet the market specifications. This method requires a special fish pond, and summer flower seedlings can also be interplanted as fish species in this fish pond every other year.
In order to solve the problem of difficulty in catching fish in bait ponds, it is also possible to promote fishing with nets.
3. Strengthen daily management.
(1) Do it? Third, see fertilization? ,? Four decisions? Hello.
Look at the water:
The color of water is mainly reflected by the color of plankton in the water. Do you want to keep the pool water? Fat? 、? Live broadcast? 、? Is it cool? . ? Fat? That is, there are many organic substances in the pond, many plankton in the water and rich nutrition. ? Live broadcast? That is, the water color changes constantly, indicating that the material circulation in fish ponds is fast; ? Is it cool? . ? Is it cool? That is, the pool water is transparent and has high dissolved oxygen. The pond water is grass green with yellow (with many zooplankton), and brown green with yellow (with many phytoplankton), indicating that the pond water is fat and beautiful; Dark green, grayish blue or blue-green indicates that the water is thin; Brown and reddish brown indicate that the pool water has gone bad. More lean water, less fat water, no bad water and timely water improvement.
Second, look at the fish:
That is, fertilization is decided according to the floating head and feeding situation of fish. Floating head at dawn, sinking immediately after sunrise, the fish sinking by the pool is slightly floating head. If the floating head is too early, the fish will not sink to the edge of the pool, or the fish will float quickly after sinking with stones. This is called severe floating head. If the floating head is serious, it means that the water quality is too fat and topdressing should be stopped.
Three days:
Fertilize according to season and weather. Be diligent in summer, be steady in summer, be heavy in autumn, have more sunny days and less rainy days, and don't do it before a thunderstorm.
Positioning: Feeding should be in a fixed position, and a straw rack or bait feeding platform should be set up to facilitate observation of fish feeding, remove residues and create conditions for prevention and control of fish diseases.
Timing: normal weather, usually 9- 10, 3-4 pm, feeding and fertilization. However, in case of sultry weather and thunderstorm, feeding should be postponed or stopped.
Quantification: the feed should be even in proper amount to prevent too much and too little.
Qualitative judgment: the bait must be fresh, not rotten and moldy, the grass should be washed fresh and the manure should be fully fermented.
(2) often patrol the pond and observe more.
(3) Frequent water injection promotes growth. In high temperature and fish season, water should be added once every 10 day to increase dissolved oxygen and improve water quality.