Dong ThapTaking land from a mango garden, Mr. Nguyen Chi Tam, 40 years old, built a tank to raise fish with specialties in the West such as loaches and red-tailed dolphins, making a profit of one billion VND per year.
Previously, Mr. Tam’s family, in Ward 6, Cao Lanh City, often caught shrimp and fish in the river to sell to wholesalers at the market. However, in recent years, aquatic resources have gradually decreased, many fish species are almost absent. He cherished the idea of using his family’s 4,000 m2 mango garden to raise specialty fish species of the Mekong River.
Mr. Nguyen Chi Tam checks the weight of loach fish before selling it. Image: Ngoc Tai
In June 2021, he used his savings to build a canvas-lined tank with a capacity of 800 m3, stocking 10,000 loach fingerlings, priced at 6,500 VND each, total cost of more than 250 million VND. Knowing the living habits of fish species, he released more red-tailed dolphins. This species mainly eats loach waste, leftover food and moss, so it costs almost no extra food and helps clean the tank.
“Economically, burbot loach is very effective because the profit is many times greater than the investment cost, the selling price is stable, unlike some other species that only need the market to increase or decrease by a few thousand dong per kilogram to lose capital,” Mr. Tam said. share.
Initially without experience, he encountered many difficulties due to the incompatibility of the oxygen pump system, water supply, and filter tank, leading to an unstable water environment and mass deaths of fingerlings. He was slow to prevent some types of fish diseases, causing a loss of 1/3 of the whole herd and lower profits than expected.
After 12 months of farming, he sold 3.5 tons of burbot loach, priced at 250,000 VND per kg. On average, one kilogram of commercial fish costs two kilograms of food (29,000 VND per kilogram). After deducting costs, his profit is about 200 million VND. He also released 100 kg of dolphin breeds, collected 800 kg, selling price of 500,000 VND per kg, profit of more than 300 million VND. “Dolphins are raised with only the cost of breeding animals, and the profit is very high,” he shared.
Loach fish raised in tanks weigh about 0.3 kg each and will be sold for sale. Image: Ngoc Tai
After the first crop, Mr. Tam built a second tank, rotating stockings 6 months apart, avoiding harvesting at the same time. Besides the two species already raised, he alternates 1-2 crops of young ling fish right before the flood season. This species has a quick turnaround time and can be harvested within a month, earning a profit of 10-20 million VND per crop. In the following farming crops, the loss rate is low. With two tanks, profits increased sharply to 800 million VND with loaches, from 500-600 million VND from dolphins.
After more than two years of farming, Mr. Tam realized that snakehead loach and dolphin are not difficult to raise. The important thing is that the water must be clean, have enough oxygen, and prevent diseases at the right time with herbal medicines. In addition, the aquarium needs a lot of shelter for the fish to rest, grow quickly and get sick less.
Initially, he used net beams for the fish to enter, but later discovered that their skin was easily scratched, so he switched to cages made of bamboo, put together into many layers. He jokingly called the bamboo cages the “house” of the fish. Any animal that can compete in a bamboo cage usually grows faster.
To avoid flooding the market, when the fish were 8 months old, he gradually trimmed and sold the larger fish to restaurants in the city or to customers hosting parties. In the tank he placed a number of traps, which only need to be removed to sell dozens of kilograms at a time. This method of harvesting also limits the impact on the entire school of fish. When the density gradually decreases, the remaining ones have more space to grow and quickly gain weight.
Each of Mr. Tam’s fish tanks has a capacity of about 800 m3. Image: Ngoc Tai
Not stopping at income from fish, Mr. Tam takes advantage of tank wastewater to pump into the mango garden, providing protein sources for the trees (fish feces, leftover food). On average, he releases water into the garden once a month. Water along the canal seeps into the soil, helping garden owners save on watering and fertilizing costs.
Another benefit, wastewater produces worms – a favorite food of chickens. The garden owner raises more chickens to take advantage of by-product resources. “I don’t think fish farming is very profitable but waste small things. Collecting many sources, the new model is sustainable,” he said.
Mr. Vo Thanh Tuan, Vice Chairman of Cao Lanh City Farmers’ Association, said the above model is suitable for urban agriculture, where the area is small. In addition, by taking advantage of many sources of agricultural by-products at the same time, the model meets circular criteria and increases revenue. “The Farmers’ Association will evaluate Mr. Tam’s model before deciding to encourage replication,” Mr. Tuan said.
Cao Lanh City currently has 3,400 hectares of mangoes concentrated in suburban communes and wards, ranking second in Dong Thap (total area of 14,000 hectares).
Model of raising snakehead loach mixed with red-tailed dolphin under a mango canopy. Video: Tran Thanh
Ngoc Tai