preface
The California perch, scientifically known as the largemouth bass, has smooth silver scales and a yellow tail, and can reach an adult length of up to 50 cm and weigh more than 10 kg. Known for its strong vitality, this fish is adaptable and can survive in a variety of water temperature and salinity conditions.
They are apex predators, feeding on small fish and crustaceans, with sharp teeth and a flexible body with a fast swimming ability, making them excellent predators and also popular fishing targets.
This fish is loved for its delicious meat, high quality protein and healthy fats. By farming California perch, which provides a stable supply for consumers and reduces dependence on natural resources, natural ecosystems can be preserved.
Choice of ponds
When choosing the right pond for farming, the choice of water source is crucial, sufficient water sources ensure the water supply demand during the culture process, and facilitate the discharge of wastewater to ensure the freshness of the water body. The leakage resistance of the pond should also be paid attention to to avoid water waste and environmental pollution.
The water depth should be more than 1.5 meters, which helps to maintain a stable water temperature and water quality, the transparency should reach 30 to 40 cm, which can provide enough light for the farmed organisms to carry out photosynthesis, the pH of the water should be between 6.5 and 8.6, which is the range to which most aquatic organisms are adapted, and the dissolved oxygen concentration should be kept above 5 mg/L to ensure sufficient oxygen supply in the water body.
In addition to water quality, the environmental conditions of the pond also need to be carefully considered. Ventilation and light transmission is the key to keeping the water fresh, conducive to gas exchange and water circulation, the choice of pool bottom is also very important, loam is the ideal choice, it provides a suitable growing environment, and contributes to the stability of water quality.
Proper area planning is also necessary when pond culture is carried out. A moderate area (2 to 5 acres) helps to maintain the relative stability of the water body, including aspects such as temperature and water quality. Disinfection of ponds is necessary before stocking seeds and can be cleaned by using quicklime or bleaching powder.
Selection of fingerlings
In pond fish culture, robust, disease-free fry need to be stocked, special attention needs to be paid to the water quality conditions of the pond before releasing the fry, suitable water quality needs to be cultivated in advance, and water quality indicators are regularly monitored to ensure that they are within the ideal range.
Before stocking, you should choose a day with stable weather and try to do it in the morning of a sunny day, when the dissolved oxygen content in the pond will be higher and the temperature change will be small, which will help the fry to better adapt to the new environment.
California bass can also be observed in a purse seine for a period of 24 hours, through which any abnormalities such as disease, injury or behavioral abnormalities can be detected in time. Only when the fish are performing normally during the observation period can they be safely stocked.
Stocking of fry
In order to obtain high-quality California sea bass fry, it is necessary to select seeds that are neatly sized, robust, have no surface damage, and exhibit ferocity and swarming ability.
Some precautionary measures can also be taken before releasing the fry into the pond. A brief medicated bath with 3% to 5% saline or a soak with a 20 mg/L solution of potassium permanganate can help prevent common fish diseases.
It is also possible to improve water quality and increase economic benefits through polyculture with other fish species, which can be cultured with fingerlings such as silver carp, bighead, crucian and cochineal, which can promote the circulation and stability of water bodies, help reduce waste and provide additional sources of nutrients. It should be noted that the individual size of the fingerlings in the set should be 2 to 3 times larger than the California bass fry to avoid predation by California bass on other fish.
Each 667 square metre culture area can stock approximately 2,000 to 3,000 California bass seedlings, with some silver carp, crucian and bighead carp in appropriate numbers. This combination will lead to better farming results, increased economic efficiency and a sustainable fish farming experience.
Management of water quality
Every half month, a full pool splashing operation effectively cleans the water body and improves transparency, and quicklime can be used to regulate water quality and ensure a suitable environment. Every 667 cubic meters of water, add 1015 kg of quicklime to keep the pH value of the water body in the range of 7.0~8.5, which helps to maintain the stability of the water body.
In the high temperature period in summer, it is especially necessary to pay attention to the replenishment of the water body, and add 15~25 cm of new water every 10 days, which can effectively replenish water and maintain the water level to alleviate the impact of summer water evaporation.
It is also possible to use the aerator scientifically, by agitating the water body, the aerator can promote the convection mixing of the upper and lower water bodies, thereby increasing the concentration of dissolved oxygen. In order to prevent the occurrence of hypoxia, it is recommended to turn on the aerator for 10 hours a day in the high temperature season, that is, from 22 pm to 5 am the next day, and on sunny days it can be turned on from 12 noon to 3 pm, and on rainy days, it is necessary to extend the oxygen increase time appropriately according to the specific situation.
To improve substrate and water quality, substrate improvers, EM bacteria, bacillus, and photosynthetic bacteria can be used regularly. The use of these beneficial microorganisms can promote the decomposition of substrate and the degradation of harmful substances in water bodies, thereby improving water quality. At the same time, it is also necessary to observe the number of zooplankton in the pool water, and once the number of zooplankton is found to be excessive, measures are taken to remove it in time to prevent it from consuming a large amount of oxygen.
Choice of feed
Young California perch feed mainly on cladocerans, copepods, diptera larvae and pupae, as well as amphipods, and as they grow, they gradually turn to prey on small fish, and in captivity, it is necessary to provide appropriate feed for California bass.
The bait for farmed California perch mainly consists of surimi processed from chilled fish, puffed feed and soft pellet feed. The types and qualities of chilled fish vary from season to season, and seven-star fish is a popular chilled fish that is widely used by farmers for its high protein content. However, the instability of the quality and origin of chilled fish, as well as the difficulty of preserving and carrying pathogens, make it ineffective feed, and 4 to 5 kg of chilled fish needs to be fed to one kilogram of California bass.
In order to solve this problem, puffed feed and soft pellet feed can be used, and the puffed feed can be treated with high temperature and high humidity, which can reduce the anti-nutritional factors in the raw materials and improve the digestion and absorption efficiency of California bass.
High-quality puffed feed can not only meet the nutritional needs of California bass, but also significantly improve its feeding efficiency and intake, promote its rapid growth, and reduce feed waste and feed coefficient.
Soft pellet feed is also a commonly used feeding method, soft pellet feed is made of a mixture of surimi and marine fish concentrate, which has the characteristics of easy processing and feeding. During the hot season and pre-emergence, soft pellet feed can reduce the cost of California bass farming and increase the yield per unit area.
The way of feeding
California perch are usually domesticated seeds that have adapted to captivity and can receive feed directly. During the feeding process, there are some important principles that can be followed to ensure their health and growth.
In order for California bass to develop the habit of feeding in a fixed position, feed can be fed on fixed feeding grounds and feeding tables. Before feeding, tapping the pot to make a noise can help attract their attention and allow them to gather in a specific feeding position, choose a location with a wide water surface, near the water inlet, and avoid pond corners so that California bass can easily access food.
It is also necessary to develop a reasonable feeding schedule according to the living habits and needs of California bass. At the beginning of stocking, feeds are given 5 to 6 times a day, then gradually reduced to 3 doses. If the water temperature is too high in summer, the feeding frequency can be adjusted to 2 times, the feeding time should be kept between 20 and 30 minutes, and the feeding speed should follow the principle of "slow, fast, slow" so that the California bass can fully feed without wasting feed.
In general, the feeding amount can be halved on the first day after fingerling stocking, and then return to normal feeding on the third day, usually between 3% and 5% of the body mass of the fish, and can be increased or decreased according to weather conditions, water quality changes and fish feeding. In extreme weather conditions, such as high temperatures or poor water conditions, feeding may need to be suspended to avoid stress and digestive problems for the fish.
Day-to-day management
California perch is a ferocious carnivorous fish that sometimes acts cannibalistically, and it is necessary to periodically classify the fish and put the same size fish in the same pond to avoid the phenomenon of large fish eating small fish. This work should be carried out in the morning when the weather is good, avoiding the rearing of fish in hot or cold times to prevent the fish from dying only due to the stress response.
Care also needs to be taken to fine-tune water quality and avoid the use of water-modifying drugs in large quantities in a short period of time, as overuse may lead to deterioration of water quality. In addition, the impact of the bottom change on water quality is long-term and will not be immediately effective, so the bottom correction work needs to be carried out gradually.
Fish ponds are visited daily to observe fish movements and changes in water quality. Pool water should be avoided to be too turbid or fertile, and transparency should be kept at an appropriate level, about 30 cm.
At the same time, it is necessary to clean up the garbage, sick and dead fish and residual bait in the fish pond in time, especially in the high temperature season, it is necessary to increase the frequency of pond patrols, find problems in time and take measures to reduce losses.
In addition, archiving is also an important task. The number of fry stocked, feed feeding, growth and control of fish diseases in ponds or cages should be recorded. Such a record helps to solve problems in a timely manner and accumulate experience for future aquaculture production.
When buying exotic fry, it is important to carry out inspection and quarantine to prevent viruses and bacteria-carrying seeds from entering the farming environment. It is also very important to strengthen daily feeding management and improve the immunity of the fish itself, once abnormal phenomena such as black body color, isolated swimming, loss of appetite, etc., should be diagnosed in time and corresponding treatment measures should be taken.
Author's point of view
As a precious edible fish, its meat quality and delicate taste are loved by consumers, however, wild California bass has limited resources and cannot meet the growing market demand.
Through the rational design of aquaculture ponds, control of water quality, temperature and oxygen and other parameters, provision of appropriate food and feed management, as well as disease prevention and control and water quality monitoring, are all important factors to ensure the efficiency and sustainable development of aquaculture, these experiences can provide reference for the cultivation of other fish, promote the healthy development of the entire aquaculture industry, and are of great significance to ecological environmental protection and sustainable development.
In addition to this, some potential problems can also be identified during the farming process. For example, issues such as water use, waste treatment and ecosystem impacts require enhanced environmental protection and sustainable management, which is essential to achieve green and sustainable development of aquaculture.
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