Key Technical Points for Pond Culture of Freshwater Pompano
The freshwater pompano is a large economically important fish of tropical and subtropical regions, valued both as food and as an ornamental fish. It has the advantages of omnivorous feeding habits, fast growth, large individual size and few diseases. In pond culture it generally lives in the middle and lower layers of the water body, and its tolerance to low oxygen is stronger than that of ordinary fish, with dissolved oxygen required to be above 3 mg/L. Its feeding habits lean toward animal-based feed, and under artificial rearing it can be fed soybeans, pelleted feed, animal offal and so on. The optimum growth temperature is 24-32°C. The main culture period is from May to September. Stock 50 g fingerlings in May, and after 3 months of growth they can reach the market size of 500-700 g.
Pond Conditions
Ponds of 1-10 mu can all be used for culture. The water depth should be more than 1.5 m, the mud at the pond bottom about 10 cm thick, the water quality fresh, the water source sufficient, and drainage and irrigation convenient. Equip each pond with one 3 kW aerator. One week before stocking the fingerlings, disinfect the pond with quicklime.
Selection and Purchase of Fry and Fingerlings
Purchase the culture fry and fingerlings in early May. To achieve an early market listing, the fingerling size is generally required to be about 50 g.
Stocking Density
For primary culture of freshwater pompano, generally stock 700-800 fish per mu, with 50-100 large-size silver carp and bighead carp as a secondary species; for secondary culture, stock 300-400 freshwater pompano per mu.
Feed Feeding
During the rearing period, hard pelleted commercial feed can be fed, with a particle size of 3-4 mm and a crude protein content of 30%. Use an automatic feeder for feeding, feeding twice a day at fixed times, namely 9 a.m. and 3 p.m. Soybeans can also be used for feeding; soak them in water 6-8 hours before feeding, until the center of the soybeans swells to plumpness. Animal offal such as chicken intestines can also be used for feeding. The daily feeding amount is adjusted according to changes in water temperature, water quality and fish growth, generally accounting for 3%-10% of the total body weight of the fish in the pond. Every 1-2 days, supplement with some green feed rich in vitamins, such as melon and fruit peels and vegetable leaves.
Daily Management
Persist in patrolling the pond every morning and evening, checking the fish's feeding, activity, growth and water quality changes, and take timely measures to solve any abnormalities found. Change the water every 5-7 days to keep the water quality fresh; persistently carry out the "four fixed" feeding work, and never feed moldy, spoiled or rotten feed. In the high-temperature weather from June to September, run the aerator for 1 hour at noon every day, and take measures in advance when the weather changes abruptly, such as muggy weather, to prevent the fish from surfacing for air.
Disease Prevention and Control
The freshwater pompano has relatively strong disease resistance; usually when the water temperature is above 25°C it rarely gets sick, and the survival rate is generally above 95%. When the water temperature is around 20°C, it is often infected by pathogenic bacteria or suffers from parasitic diseases such as ichthyophthiriasis, dactylogyrosis and trichodiniasis. Ichthyophthiriasis in particular can cause mass death of the fish within a short time if not treated promptly, so disease prevention and control work must be done carefully. The use of drugs such as trichlorfon and malachite green is prohibited.