Key Points and Methods of Freshwater Grouper Farming Explained

Freshwater grouper was introduced to Taiwan, China in the last century and later developed into a freshwater fish species commonly farmed across the country. It can serve as both an ornamental fish and an edible commercial fish. So today, the editor will walk you through the farming techniques for freshwater grouper.

1. Living Habits

Freshwater grouper can grow in fresh water and also in seawater with a salinity below 10‰. Its suitable temperature range is between 25-30°C. When the water temperature drops to 20°C, feeding will decrease noticeably; when the water temperature drops to 15°C, the body loses balance. Therefore, areas where the pond water drops below 15°C in winter are not suitable for farming. If farming is desired in these areas, a heater can be used. During the overwintering period, the water temperature for freshwater grouper growth should be above 19°C. Freshwater grouper has a diet that tends toward carnivory, and the carnivorous trait is strong at the fry stage, mainly feeding on zooplankton.

2. Breeding Habits

The spawning habits of freshwater grouper are the same as those of tilapia. They dig many spawning nests at the bottom of the pond. Spawning generally takes place in the afternoon. After spawning, the female fish mainly guards the fertilized eggs, and the male fish also guards cooperatively. However, as the embryo develops, the guarding behavior becomes weaker and weaker. The eggs of freshwater grouper are oval and opaque yellow-dark green in color. The eggs are spread out on the pond bottom and rarely overlap. A female fish weighing 140 grams lays about 3000-4000 eggs each time. At a water temperature of 26-29°C, the fertilized eggs can hatch into fry after 48 hours.

3. Fry Rearing

1. Disinfection and Stocking

Before fry rearing, freshwater grouper ponds should be cleaned and disinfected with quicklime and the water quality should be fertilized. Before stocking fry, test the water first. The specifications of fry stocked in the same pond should be consistent; otherwise, fighting will occur, which is not conducive to fry growth. The stocking density depends on the bait, the level of farming technology, and the rearing specifications.

2. Water Quality Management

Freshwater grouper fry rearing easily deteriorates water quality, so change the water once every 3-5 days, with each water change being 1/4 of the total. Aquatic plants can be transplanted into the pond to purify the water quality, and at the same time it is convenient for the fry to hide and feed. When there are large differences in fry specifications, sieve and separate them for rearing.

4. Bait Feeding

1. Feeding Fry

Freshwater grouper has a diet that tends toward carnivory, so when fry are put into the pond they feed on zooplankton. As the fry grow, their food intake increases, and the zooplankton in the pond gradually decreases. Therefore, it is necessary to apply fertilizer to cultivate zooplankton, or add feed to meet the growth needs of the grouper.

2. Fry Food Training

When freshwater grouper fry reach more than 3 cm, food training can begin. Feed minced fish on the feeding platform. After 3 days, add a small amount of compound feed mixed with minced fish, then gradually increase the compound feed until it is entirely compound feed. This can make the fish less dependent on zooplankton and make rearing more convenient.

3. Feeding Management

The daily feeding amount for freshwater grouper is about 20% of the fish body weight. The protein content of the compound feed should be 35-40%, and animal protein should be above 25%. Other plant protein raw materials can be added, so as to meet the nutritional needs of freshwater grouper.

5. Adult Fish Farming

1. Small-Scale Polyculture

Freshwater grouper can be polycultured in small amounts in ponds. Polyculture about 25-50 freshwater grouper per mu of water surface. After half a year of farming, the average body weight can reach more than 300 grams. After the body size becomes too large, sieve and separate them for rearing.

2. Pond Main Farming,

Freshwater grouper can be polycultured with tilapia, grass carp, crucian carp, etc., at 150-200 fish per mu of water surface, with 300 polycultured fish. After half a year of farming, the average body weight can reach about 200 grams. After the body size becomes too large, sieve and separate them for rearing.

The above is the freshwater grouper farming technique summarized for you by the editor of Tuliu.com. We hope it can help you!