Breeding scad with nano-aeration technology

Currently, many farmers in the Mekong Delta raise scads in earthen ponds or in wooden rafts, which bring about high economic efficiency. However, this is a new farmed object with high economic value in the market because now the carp is mainly living in the wild.

Mastacembelus favus is a freshwater fish with a dark green or black-gray body, with many round or oval yellow spots on the body; Dorsal, anal, and pectoral fins with small black spots, no pelvic fins. When young, the main food of the loach fish is worms, insect larvae, and small crustaceans. When large, the fish eats adult insects, shrimps, small fish and organic matter.

In the wild, the growth of scads after 1 year of age can reach 150 - 250 grams/fish, 18 - 25cm long; after 2 years reaching 450 - 500 grams, 35 - 40cm long. They mature and reproduce after 2-3 years; Males are usually larger than females, despite being of the same age. Females have a reproductive capacity of 4,500 - 7,500 eggs/time; Eggs are small, yellow in color.

Fish usually spawn in the rainy season, the water is cloudy, from June to September; spawning places are caves, crevices of underground rocks along rivers and streams. In the rearing process, if fresh food is used, especially worms, the growth rate and survival rate of the locust will be higher than that of other foods.

Mr. Le Van Phuc in An Long commune, Tam Nong district (Dong Thap) has taken advantage of the pond water surface in rice fields to successfully implement the model of raising scads. Initially, Mr. Phuc renovated 2 ponds with an area of 2,000 m2 in the rice field to raise 10,000 fish.

He stocked larva in nursery ponds and fed the fish with food such as worms, insect larvae and high protein industrial pellets. More than a month of care, he mass-cultivated in 2 earthen ponds and continued to use industrial pellets, increasing the amount of food according to the growth of the fish. 

Every day, he changed the pond water once, taking care of the fish carefully. At the same time, mix vitamins and some minerals into fish food to increase resistance and help fish gain weight quickly, less disease.

After 9 months of farming, Mr. Phuc harvested commercial carp with an average weight of 300 - 500 grams/fish, selling for 350,000 - 370,000 VND/kg. After deducting investment and care costs, Mr. Phuc still made a profit of nearly 100 million VND in the first farming season. 

Up to now, Mr. Le Van Phuc has expanded his pond to 4,000 m2 and established a cooperative group for raising scads in An Long commune. Mr. Phuc happily shared: On average, 3 kg of feed will produce 1 kg of commercial carp. On average, his family harvests 2 times a year. Each batch collects from 700 - 800 kg of fish, the income is from 250 to 300 million VND.

As for Mr. Tran Hong Thai, in Vinh Hoa commune, Tan Chau town (An Giang) has many years of experience in raising pangasius fingerlings for more than 30 years, but in the last 2 years, raising pangasius fingerlings has encountered many difficulties due to Affecting market prices, Covid 19... Facing these difficulties, Mr. Thai decided to switch to commercial farming of clear scads placed in earthen ponds combined with nano-aeration.

Mr. Thai shares the secret of successfully raising scads with nano-aeration technology to help the fish grow faster and with less head loss: With a pond area of 1,000 m2, Mr. Thai arranged to raise in 5 cages, 16m2 each. Each swing has an aeration arrangement using nano technology.

After pumping water into the pond with a depth of 3.5m, for 15 days, 6,000 seeds were released, with an average weight of 5 grams/fish (200 fish/kg), 1,500 fish in each round. After 2 days start feeding the fish. In the first week, feed the fish twice a day, each time is 3kg of industrial food (40% protein).

Industrial feed is pureed and then added with digestive enzymes and vitamin C, mixed well and placed on the floor for fish to eat. While feeding the fish I still aerate normally. Outside, Mr. Thai also released a few more cheetahs, barnacles and pangasius so that they could take advantage of the leftover food of the scads. After more than 1 month of farming, the average weight was 70 fish/kg.

“Using nano-aeration technology in ponds is a very cool technology. After more than 1 month of stocking, the water in my pond is still good, no need to change the water, only 2 more times since rearing, the water color is beautiful, the fish is healthy and not sick. With 6,000 breeding stock after 1 month, the loss is less than 10 animals. With a 24-hour continuous aeration system, I monitor the amount of electricity consumed for 1 hour is 0.4 KW of electricity, this system can adjust the aeration strong and weak depending on what you want,” said Mr. Thai.

Although it was just over a month of rearing, I noticed that the fish grew very quickly, after more than a month, the fish was one and a half times larger than the original weight. With this large rate, in about 6 months, Mr. Thai will have 300-400 grams of scads sold in the market.

In particular, Mr. Thai's model of raising catfish does not change the water at all, but the water quality is always good, so it limits the discharge of water into the outside environment. The model has contributed to the protection of environmental pollution from pond wastewater.