How to raise red drum (Sciaenops ocellatus)? Detailed explanation of the key points of grow-out techniques

Pond culture

(1) Conditions and requirements of the culture pond. The area of a grow-out pond is generally 5-10 mu, preferably 3-5 mu, and a water depth of 1.5-2.5 m is suitable. The soil is best as sandy loam, dissolved oxygen must not be lower than 6.5 mg/l, ammonia concentration ≤0.3 mg/l, and pH 7.5-8.5.

(2) Preparation before stocking. Carry out repair and disinfection of the shrimp pond according to general marine culture specifications, fill with new water, and fertilize to cultivate water quality 7-10 days before releasing the fry. In the early stage, the water is generally filled to 70-80 cm so as to raise the water temperature more quickly.

(3) Stocking size and density of fingerlings. The general size is 1.9-4.3 g per fish. The stocking density is 1500 fish/mu.

(4) Management during the grow-out period. Patrol the pond frequently and strictly control water quality, and take timely measures when problems are found; control the daily feeding amount, generally feeding 2-5% of the fish body weight. Generally feed twice a day, once at 8-9 am and once at 3-4 pm; achieve feeding at a fixed point, at a fixed time and in a fixed amount; pay attention to the drainage and injection of pond water, keep the water level at about 2 m, and the daily water exchange volume at 20%; pay attention to pond hygiene and disease prevention and control, promptly clean up weeds on the pond banks and in the pond, large algae and feed residues, regularly feed drugs to prevent disease, and when disease is found, promptly identify the cause and take corresponding measures; carry out regular inspections and keep good records.

Cage culture

(1) Stocking size and density. Red drum cage culture can be divided into two types: one is the intermediate rearing stage of fry and fingerlings in sea cages; the other is the grow-out stage. The best stocking size for the intermediate rearing stage of fry and fingerlings is 2.5 cm in body length. At 23-28°C, they can grow to about 6 cm in about 30-40 days. The maximum stocking density is 1500 fish/m3. In the grow-out stage, the stocking density of fingerlings 6 cm in body length is 60-100 fish/m3, preferably 20-30 fish/m3.

(2) Daily management of cages. Safety inspection, strictly prevent fish from escaping. During cage culture, the safety of the cages must be checked frequently; ensure no fish escape, and keep good rearing records, including fish activity and feeding conditions, water temperature measurement, salinity measurement, mortality, weather changes, fish growth (measured once every 10-15 days), and cage damage and repair.

(3) Removal of attachments on cages. The main attachments on cages are algae, bryozoans, sponges, sea squirts and silt. To remove these attachments, manual washing and brushing can be used, and preferably a water spray gun or submersible pump can be used to wash off the dirt on the cages with a strong water flow. If that really does not work, the only option is to replace the cages.

Feeding. The feed mainly includes two types: trash fish and compound feed. When feeding trash fish, its freshness must be ensured. The daily feeding amount is 2-5% of the fish body weight, fed twice a day.

Disease prevention and control of red drum (Sciaenops ocellatus)

Because red drum (Sciaenops ocellatus) was introduced for a relatively short time, no diseases specifically targeting red drum have been found so far, and therefore research is also relatively limited. This is also one of the reasons why red drum is easy to raise.