CATDOLL : CATDOLL: How to breed freshwater grouper? Are there any good methods for breeding and management?

1. Morphological characteristics

Freshwater grouper has a spindle-shaped body with an upper mouth. There are eight black stripes on each side of its trunk, with darker pigment blocks in the center of the vertical black stripes. The pectoral fins are light yellow, and the pelvic fins, dorsal fins, and anal fins all have black stripes. The black stripes on the caudal fin are perpendicular to the body. In addition to the black and white stripes, the body surface of the adult fish is slightly yellow, and the body color changes adaptively with the external water environment and the reproductive period. When breeding, the male fish is darker in color, while the female fish is lighter in color with yellow. The pelvic fins are located on the chest, and the caudal fin is rounded and has a reproductive process. The eye sockets of young fish are red, while those of adult fish are silver-yellow. The scales are round and relatively large. The lateral line scales are intermittent.

2. Living habits

Freshwater grouper is a tropical fish that grows in freshwater and can also grow in seawater with a salinity of less than 10%. Its suitable temperature range is between 25 and 30℃. When the water temperature drops to 20℃, its food intake decreases significantly. When the water temperature drops to 15℃, its body loses balance. Therefore, areas where the water temperature drops below 15℃ during winter are not suitable for breeding this fish, unless there are insulation measures. It is better to keep the water temperature above 19℃ during the winter. Freshwater grouper is a bottom fish that tolerates low oxygen and has strong disease resistance. Fish diseases rarely occur during the breeding process. It can be mixed with tilapia and crucian carp to remove small fry in the tilapia and crucian carp ponds to achieve high quality and high efficiency.

3. Breeding

Seedling cultivation technology

Requirements for fish fry land: Earthen ponds are preferred for freshwater grouper fry breeding ponds, but outdoor cement ponds can also be used. Generally, the area of ​​a single pond is 50-100m3 and the water depth is 1-1.5 meters. Before stocking the fry, drain the pond water, thoroughly clean and disinfect the pond with quicklime, and apply sufficient basal fertilizer to improve the water quality so that the fry can eat natural bait when they are put into the pond.

Stocking of fish fry: Before stocking fish fry, water should be tested. The specifications of the fish fry in the same pond should be uniform and of the same size. The stocking density depends on the bait, the level of aquaculture technology and the cultivation specifications. The general stocking density is about 100 fish/m3. Before the fish fry are put into the pond, they should be soaked in sop salt water for 15-20 minutes.

Feeding: When freshwater grouper fry are put into the pond, they feed on zooplankton. As the fry grow, their food intake increases, while the zooplankton in the pond gradually decreases. At this time, one can cultivate zooplankton through topdressing, and the other can increase the feeding of soy milk. After 15-20 days of cultivation, when the fry are more than 3 cm, their feeding habits begin to change. At this time, you can feed them with minced fish on the feeding table to train them to eat. After 2-3 days, add a small amount of artificial compound feed to mix with minced fish and feed them. Later, gradually increase the proportion of artificial compound feed and reduce the amount of minced fish until all artificial compound feed is used. The daily feeding amount is about 20% of the fish body weight, and feed 3 times a day.

Cultivation Management

Adjust water quality: During the fry cultivation process, the feces and bait left over from fertilization and feeding are most likely to deteriorate the water quality. Therefore, the water should be changed every 3-5 days, with the amount of water changed each time being 1/4 of the pond water. Some aquatic plants such as duckweed or water hyacinth can also be transplanted into the pond to purify the water quality and facilitate the hiding and feeding of the fry.

Timely separation: When the size of the fry grows differently, they will eat the smaller ones. Therefore, they should be screened and separated in time. The size of the fry in the same pond should be consistent to avoid affecting the survival rate of the fry.

Daily management: mainly patrolling the pond and observing the fry’s feeding, activities, water color changes, etc., so as to adjust the feeding amount in time and prevent fish diseases.

Requirements for fry land: Freshwater grouper fry breeding ponds are preferably earthen ponds, and outdoor cement ponds can also be used. Generally, the area of ​​a single pond is 50-100m3 and the water depth is 1-1.5 meters. Before stocking the fry, drain the pond water, thoroughly clean and disinfect the pond with quicklime, and apply enough base fertilizer to fertilize the water quality so that the fry can eat natural bait when they are put into the pond. Before stocking the fry, the water should be tested first. The specifications of the fry in the same pond should be neat and consistent in size. When the freshwater grouper fry are put into the pond, they feed on zooplankton. As the fry grow, the food intake increases, and the zooplankton in the pond gradually decreases. Adjust the water quality: During the fry cultivation process, due to fertilization and feeding, the remaining feces and bait are most likely to deteriorate the water quality. For this reason, the water should be changed every 3-5 days, and the amount of water changed each time is 1/4 of the pond water. When there are large differences in the growth specifications of the fry, because they have the habit of eating small ones, they should be screened and raised in time. The fry in the same pond should be kept in the same size to avoid affecting the survival rate of the fry. Daily management mainly involves patrolling the pond to observe the fry's eating, activities, water color changes, etc., so as to adjust the feeding amount in time and prevent fish diseases.

The breeding of grouper is very particular about the cost of artificial technology, and the value behind it is also very high. Especially for some grouper in the wild, it requires more technical and financial investment.

Farmed grouper can be farmed in small quantities in ponds, and mixed farming is better. Grouper can be farmed together with grass carp, crucian carp, and tilapia.