How to breed koi carp
Algae problem in koi ponds
Outdoor koi ponds are often rich in algae. Both the pool wall and the pool water are often covered with a layer of moss. The appearance of algae It means that there are too many nutrients in the water, which will cause the growth of algae. These algae will absorb and utilize the nutrients in the water, such as nitrates and ammonia. It can be said to be a beneficial plant-based filtration system. At the same time, we can also The water quality can be understood through the changes in these algae. Clear water quality and green algae growing on the wall of the pool mean that the water quality is stable and the algae phase is good. Moreover, these green algae are also a feast for koi carps.
But if the water quality is green, that is, planktonic algae are growing in large numbers, it means that there are too many nutrients in the water. At this time, you need to pay more attention. Be careful of algae blooms caused by insufficient dissolved oxygen in the water. Phenomenon. Because algae die in large numbers, fish will also be affected. Algae in aquariums often appear on the leaves of aquatic plants, tank walls, and filters. Some are small green dots, and some are a layer of green algae. The most serious one is black hair algae, which looks like a brush. Once algae appears, it is difficult to remove. It is necessary to frequently change the water, add algaecide, etc. After a period of treatment, the aquarium will return to its original appearance only after the algae has completely fallen off. We refer to these substances that can cause algae growth as nutritional factors in the water, including: phosphates, nitrates, etc., which mainly come from feed residues and excreta. Changing the water every 5 to 7 days and regular water quality monitoring are ways to prevent these nutritional factors from being too high. Maintaining the nitrate concentration below 5ppm and the phosphate concentration below 1ppm can effectively prevent algae in the water. Growth
Key points of management of koi in different seasons
The weather temperature changes greatly in spring, from warm to cold, and sudden cooling is easy. At this time, special attention should be paid to koi that have just been moved from indoors to outdoor breeding. When cooling down, the fish pond should be covered with plastic film to keep the water temperature stable. When winter turns to spring, it is the time when fish transition from hibernation to recovery. The fish have weak constitutions. When feeding, the amount of bait should be gradually increased, and more bait with a large proportion of plant ingredients should be added to facilitate the digestion and absorption of koi.
The water temperature is high in summer. In order to maintain the normal growth of koi, it must be covered with plastic shade nets to maintain a suitable water temperature. Otherwise, phytoplankton and green algae will multiply in large numbers and the water quality will be turbid, affecting the growth of koi. At the same time, ultraviolet rays have a certain impact on the color enhancement of koi. According to statistics, the sunlight illumination in Beijing is 8,000 to 12,000 lux; after being covered with plastic shading nets, the illumination is reduced to 5,500 to 5,800 lux. The light at this time is relatively soft, which is suitable for the growth of koi.
In the autumn of August and September, the weather is sunny and the air is crisp. It is the season with better weather in Beijing. The air temperature and water temperature will drop significantly, which is the most suitable season for the growth of koi. You can feed more feed to make the fish full. It is best to increase the proportion of animal protein in the bait ingredients. In areas where conditions permit, you can feed some silkworm pupae to keep the koi fat and strong for the winter.
When the temperature drops to 0°C in winter, koi will swim slowly and eat less. The koi should be moved to an indoor fish pond in time to survive the winter. The indoor water temperature should be maintained at 2°C to 10°C. The focus is on heat preservation, proper feeding, trying to prevent the fish from becoming thin and preventing the occurrence of fish diseases. From November to March of the following year, the frequency of management work such as water changes, water additions, and dirt removal should be reduced to a minimum. When feeding, more easily digestible bait should be added, mainly to ensure that koi carp can survive the winter safely.
Koi carp breeding and selection technology
Koi carp is a carp that is artificially bred to have color, markings and can be viewed by people. It was introduced to Japan from China and became an ornamental fish after mutation and improvement in Japan. After long-term continuous improvement and selection, 13 strains of koi have been formed, including red and white, Taisho three colors, Showa three colors, and gold. Koi is known as the "living gem in the water" and the "king of ornamental fish" due to its strong physique, bright colors, changeable patterns and elegant swimming styles. I started research on the introduction and artificial breeding of koi in early 2003, and achieved initial success after May: approximately 5 million eggs were laid, more than 2.1 million fry were produced, and 320,000 high-quality koi fry were obtained after selection. . The test results are now summarized as follows.
Materials and methods
1. Main facilities
There are 10 cement pools in the nursery room, each with an area of 3m×8m and a water depth of 1.2m. The water source is river water after being filtered twice with sand, and is equipped with heating and gas supply facilities.
Earth ponds include: 0.1hm2×2 mouth, 0.2hm2×2 mouth, 0.33hm2×3 mouth, 0.55m2×5 mouth, 0.6m2×2 mouth, the maximum size is about 5.34hm2, the small earth pond is square, and the large one is square. It is rectangular, with a water depth of about 2.5m. Each pond is equipped with a 1.5kw waterwheel-type aerator.
2. Selection and cultivation of broodstock
1. Selection of broodstock
The selected broodstock strains are pure and excellent, with obvious strain characteristics, strong and flexible physiques. A koi that swims gracefully and has no defects, and its body is smooth and disease-free. The age of the parent fish is above 4 years old for females and above 3 years old for males. The male to female ratio is 4:3. We imported broodstock: 13 groups of red and white, 21 groups of tricolor, 2 groups each of gold and platinum, and 2 groups of other strains. Among them, 41 are female and 31 are male, totaling 72.
2. Intensive cultivation of broodstock
After purchasing broodstock on January 22, the males and females were cultured in separate pools, with micro-flowing water, and carp were fed with floating bait and silkworm pupae. The total food intake was It is 2%, and the amount of silkworm pupae increases or decreases according to the gonad development of the fish. The temperature began to gradually rise in early March, rising by 1°C in 3 days, and the water flow was stopped. The slight aeration disappeared at 24. The dissolved oxygen was 4-5mg/l, and the ph value was 6.3-7.
3. Pairing for induction of labor and preparation of fish nests
In order to increase the rate of high-quality offspring of koi, we classify and pair koi according to their strains, and then use drugs to induce labor. Drugs include lrh-a2, dom, hcg, and the dosage of male is halved. Put it into a cement pool to wait for delivery. Since koi eggs are sticky and sinking eggs, strings of poplar roots need to be hung in the spawning pool to serve as
fish nests.
4. Spawning and hatching
The oxytocin effect period of broodstock is generally 7-12 hours. After the oxytocin injection is started at 13:00 noon, spawning begins at night. The whole process Always inflate. Pay attention during spawning and replace the poplar roots immediately after they are filled with fertilized eggs. Concentrate the poplar roots covered with fish eggs into the incubation tank for centralized incubation. Inflate and maintain the water temperature at 20%, and disinfect with 0.2-10 methylene blue. The film can come out in 3 days.
5. Cultivation of juvenile fish
Clean the pond 7 days before the broodstock spawns, apply 100kg of cow dung every 0.0667hm2, and then use 100kg of quicklime (every 0.0667hm2) Disinfect and add 50cm of water after 7 days. Generally, the number of rotifers and cladocerans in the pond reaches its peak after 10 days, which can just meet the bait needs of the fry when they open their mouths.
Put the poplar roots with fish eggs directly into the pond the day before the fry emerge, and let them hatch naturally. After 3 days, the fry will start to eat when they start to swim horizontally. At this time, they will be cultured in the pond. Rotifers and cladocerans are mainly fed, and soy milk is supplemented. After 15 days, soy milk is the main food. After 25 days, soybean cake powder is fed until the fry grow to 5cm. Enter the fry selection and separation stage.
6. Selection of koi carp
When the fry grow to about 5cm, the body color of koi carp has fully appeared. At this time, the selection of koi carp can be carried out. The standards are: On the basis of selecting healthy fry standards, we then select the best ones according to the strain standards of koi. The fry are required to have obvious strain characteristics, strong physique and bright color. No spots.
Results
1. Prenatal cultivation of broodstock
After 76 days of cultivation, 2 fish died before induction of labor, and the survival rate was 97.22%. In the whole process, the early stage (January 22 to February 15) is the indoor room temperature introduction and breeding stage; the middle stage (February 16 to March 20) is the parent nutrition intensive cultivation stage; the late stage (March 21 to April July 8) is the stage of artificial temperature control gonad maturation.
2. Mating, spawning and hatching
After drug induction, the drug effect period of the parent fish is 10 hours, and the spawning begins at 22:00 in the evening. It reaches its peak at 2:00-3:00 in the second half of the night and basically ends at 5:00-6:00 in the morning. The eggs are laid by about 5 million eggs (250 eggs are laid by the eggs, and 7 plants are randomly sampled, with an average of about 20,000 eggs per plant). The egg diameter is 1.6-1.8mm, the fertilization rate is 80%, the membrane emergence rate is 75%, and approximately 3 million seedlings will emerge.
3. Cultivation and selection of larvae and juveniles
After 50 days of fry cultivation in earthen ponds, the fry grow to 4-6cm. At this time, the body color of the koi has fully appeared. In early June, fishing began from pond to pond, and screening was carried out at the same time to retain the best and eliminate the fittest.
The screening criteria are: obvious breed characteristics, strong physique, bright color, and no spots. After 20 days of selection, more than 2.1 million fry were caught. The survival rate of larvae and juvenile fish cultured in earth ponds is 70%. 320,000 fry were obtained from the selection. The selection rate is 14.5%.
Summary and discussion
1. The male-to-male ratio of broodstock is one of the main factors affecting the spawning and fertilization rate of broodstock
Since koi is fertilized in vitro, The quantity, distribution, density and quality of sperm in the water determine the fertilization rate of fish eggs. Therefore, generally
the male-to-male ratio when breeding koi is 1:2 or 2:3 to ensure the fertilization rate of eggs. Due to other reasons, we have made the male-to-male ratio of koi this year 4:3, which is also the main reason why the egg fertilization rate this year is only 80%.
2. The success of cultivating larvae and juveniles in earthen ponds (i.e., growing ponds) is the key to completing the task of koi seed production this year
In the cultivation of earthen pond fry, we focus on The following are the following: Earth pond construction standards. Easy access and drainage, sufficient preparation, and thorough disinfection of the earth pond; the basic bait is well cultured and can be synchronized with the time when the fry emerge from the membrane, providing sufficient and palatable live feed for the fry; strengthen pond patrol management and close observation The growth and health status of fish fry, timely detection of fish diseases such as enteritis, trichozoa, etc., and accurate use of medication to treat and control, and regular use of medication for disinfection and disease prevention.
3. The selection of koi is a tedious and comprehensive technical task
First of all, we must select healthy seedlings based on the standards and then judge the koi. Standard selection. Focusing on the characteristics of the koi strain, and also considering the possible changes in the pattern and color of the koi's body surface when it grows up, only through careful analysis can we select high-quality koi. Because we have a large number of high-quality koi parents, we can strictly match males and females according to strain classification and reproduce offspring. Therefore, there is a higher selection rate in the next generation. The pass rate of koi carp above the standard grade is 14.5%. Of course, there may be errors due to the operation in the first year. (The second selection after the cultivation in November determined that there were 250,500 koi above the standard grade. The passing rate of offspring should be 11.93%). But in general, the selection rate of koi is much higher than the 5% of ordinary koi.
How to raise koi carp
Koi carp is an omnivorous fish. You can add about 10% of animal offal, snails, maggots, pupae, etc. to leftover rice, leftovers, peels, etc. Animal feeds such as earthworms are mixed and crushed to make mixed feed; bean cakes, vegetable cakes, bread crumbs, fish insects, water earthworms, turnips, duckweed, crab meat, clams, etc. can be used as bait. Portions and proportions depend on the size of the fish. You can put in a little more live snails, because after eating leftover snails, they can stay in the water to eat algae and other debris attached to the bottom and wall of the pool. They have the effect of cleaning the water quality and are good bait.
The key to raising koi well is the amount of feed you put in it. If overfeeding causes the fish to overeat, it will not only cause waste, but also cause the residual feed to rot and deteriorate the water quality, which is not only beautiful but also affects the survival of the fish. The water quality of the fish pond should be green and fresh. The remaining bait residues should be fished out in time when patrolling the pond every day. In summer, when the water temperature is high, the water should be changed every 2 to 3 days. In spring and autumn, the water should be changed once every 4 to 5 days. The water change amount is the original amount. 1/3~1/2 of the pool. Whether the koi has a strong appetite mainly depends on whether the water environment is comfortable. In spring and autumn, the water temperature is suitable and sufficient feeding can be provided. In summer and winter, when the water temperature is higher than 30°C or lower than 7°C, the amount of feeding should be reduced as appropriate. Generally, it is appropriate to finish each feeding in 15 to 30 minutes. Daily feeding The amount is 5% to 6% of the fish body weight. In summer, we usually feed once between 6:00 and 7:00 am and once between 15:00 and 16:00 in the afternoon. In spring and autumn, we feed once between 7:00 and 8:00 am and once between 14:00 and 15:00 pm. In winter, we feed once between 13:00 and 14:00 pm. times.
How to raise koi carp
1. Some basic knowledge about koi carp. The red color on the koi is called Fei, the black color is called Mo, and other colors are just called their specific color names. When choosing fish, the redder the better, the thicker the ink the better (the darker the better). Except for the pectoral fins, which are called hand fins, the other fins of the koi are consistent with the names in the book! Those who raise fish for their own enjoyment and not for other purposes are called "hobbyists", while those who specialize in fish farming are called "businessmen", for example, "fish masters" are businessmen.
2. Provide water. To raise koi well, the key step is to raise good water. With good water, koi can survive and grow easily. How to keep the water well? Generally, the water must be kept well before releasing the fish. There are several specific methods: First, let the tap water sit naturally for more than three days.
2. Put the tap water in the sun for two days. The third is to boil the tap water to 40 degrees and leave it for 8 to 24 hours. Another option is to use solar water, but since many solar cells have aging problems, the water often contains some metal oxides, so it is generally not recommended. The water raised through the above methods is generally used for all water changes and for initial fish farming. If the water is changed normally, the requirements can be appropriately reduced according to the actual situation!
3. Change the water. To raise koi well, you cannot be lazy and take chances. Generally speaking, it is required to change the water every day, about two-tenths of the water should be changed every day. Then do a major water change (full change) every 20 days, and it is best to have a trickle of water in and out at any time. The minimum requirement is to change it once a week, and change one-third of the water each time. If water mixing and serious greening occur during this period, the time for large water changes should be shortened and the amount of daily water changes should be increased. If there are no special needs, please use water with high transparency for breeding, which is conducive to viewing. Changing water is the most troublesome and daily task in fish farming, and it often requires the most patience and enthusiasm! !
4. Release fish. After buying the koi, do not put the fish into the tank immediately. Instead, put the fish in the tank together with the bag to adapt to the water temperature (do not open the bag with the fish). If you put the fish in immediately, it will easily cause the fish to catch a cold. (The bigger the fish, the easier it is to catch a cold. The main manifestations are immobility, jumping into the tank, smashing the tank, not eating, etc. However, colds in big fish will generally heal on their own, and the risk to life is small!). It usually takes about an hour to adapt to the water temperature. If the water where the fish was originally contained is not very dirty, it is recommended to put it into the fish tank together with the water. If the original water is very poor, it will easily affect the water quality. Turn on the filtration and oxygen explosion immediately after releasing the fish, so that the fish can easily adapt to the new environment quickly. Do not feed the fish within a week after releasing them. Firstly, the fish can adapt to the new environment as soon as possible. Secondly, you can observe whether the fish you bought has diseases. If you find any abnormality, please ask the boss to change it immediately (some fish will be replaced after being fed). It is difficult to determine the cause, and new fish generally do not eat food).
5. Medication and daily management. When you go to a fish store to buy fish, the boss usually recommends some medicines for you to buy together. In fact, as long as you keep the water well and put the fish in, you don’t need to put those medicines at all. Because bosses often make rumors to ask you to buy more of their stuff. In the actual process of raising fish, I do not recommend the use of drugs, because several of my friends have caused good fish to die for no reason due to the indiscriminate use of drugs. If you think about it, why should you take medicine if you are not sick? If the fish is sick, specific medicines will be selected according to different conditions, but in general, the medicines sold by merchants are not as good as Tufangzi (except for "Baibizhu"). (Except), so when fish are sick, they generally use earth-based methods, such as salt, oxytetracycline, penicillin powder and berberine. If the cause of the disease cannot be determined, it is recommended to add a large amount of oxytetracycline (according to my experience, this This trick is very effective! ), because I feel like Western medicine thinks that disease means inflammation! ! Haha... I will analyze the specific disease in detail, so I won’t go into details here! !
6. Filtration and stocking amount. In addition to filtering out impurities, the most important function of filtration is to cultivate a biochemical system to allow fish to grow healthily. If the tank is not too big, I still recommend buying a filter directly from the fish shop owner, because the owner will professionally equip you with a filtration system (it saves money to do it yourself, but many small problems are very troublesome! ). During this process, you only need to ensure that the flow rate of your filtered water pump can circulate the water in the fish tank 4 times per hour, and replace activated carbon and other substances at any time according to the degree of biochemical damage in the filter. How big of a fish tank can you raise koi carp? How many koi carp can be beneficial to the growth of koi carp? According to my experience and relevant books, it is better to raise one koi carp of about 20 cm for every 60 liters to 100 liters of water. If you want to raise them, the length of the tank should be at least 90 cm. The best water depth for raising koi is 60 cm to 250 cm, and it is said that the water depth of about 200 cm is the easiest to raise big fish. When the fish is raised in the tank close to the width of the tank, the fish must be moved to a larger tank or pond in time.
7. Choose fish.
When choosing fish, I suggest you choose what you like and what you think looks good. Don’t pursue expensive or alternative fish. This is the most important thing for novices to pay attention to, because good koi are not only expensive, but many also have color problems ( It is said that the color of many fish that sell well is revealed by feeding, and will fade over time! The price of real natural color is usually more than 3,000 yuan (the best Japanese koi of about 35 cm) and good fish cost more. Persistence also takes a lot of time, and if you don’t have time, you will be wasting a good fish). Of course, the most basic requirements for selection are that the fish must have no surface damage, a normal posture, a perfect body shape, thick crimson ink, a large nose flower, long beard and so on.
8. Koi and Feng Shui. Koi has the effect of promoting feng shui and is known as the king of feng shui fish. As early as ancient China, many dignitaries raised koi carps to promote feng shui. There is also a saying that raising fish according to the owner's horoscope will ensure safety and bring wealth. Based on the books I have read, I think some of them are quite insightful, so I would like to share them with you for reference only. If you want to raise fish at home and seek wealth, you can usually raise 3 koi, of which two are red and one is black. If it is for other purposes, it is better to keep odd numbers, and the total color of the fish should be more than three. Do not place the fish tank under the beams to act as a pavilion wall (to suppress the atrial pulse). Do not place the fish tank under the stairs, in the kitchen, or in the bedroom.