Release algae to raise shrimp, play, eat for real

HAI PHONG The reason why it is said to be "playful, real" is because raising them does not require releasing seeds or feeding them, but they still earn money every day, at least a few hundred thousand dong, at most a few million dong.

HAI PHONG The reason why it is said to be "playful, real" is because raising them does not require releasing seeds or feeding them, but they still earn money every day, at least a few hundred thousand dong, at most a few million dong.

Mr. Luong Van Nhanh (Vinh Quang commune, Tien Lang district) pushes a boat to catch shrimp. Photo: Duong Dinh Tuong.

Mr. Hoang Xuan Giang - an officer of the Agricultural Extension Station of Tien Lang District, Hai Phong City, said that in his hometown, there were two brothers sitting at a death anniversary meal, drinking wine and arguing. One said that a shrimp was a small shrimp, the other said that a shrimp was a shrimp. Neither would give in and for a decade they still haven't gotten along. If he were there at that meal, he would only ask one question: "Does a shrimp have eggs?" and the fight would be over. Because according to the principle of aquatic products, when they have eggs, it means they can't get much bigger, not even as big as the tip of a chopstick.

To raise shrimp, three conditions are required: soil quality, water quality (the most suitable water is slightly brackish), algae as a habitat, and the source of nutrients is algae. Inside the dike of Vinh Quang commune, Tien Lang district, there are long rows of ponds that meet all these conditions. Mr. Luong Van Nhanh used to raise shrimp for hire for pond owners, but due to inefficiency, they all gave up. Seeing an opportunity, in 2020 he rented a pond of more than 1 hectare to raise himself, earning a profit.

He said that in the past, no one in aquaculture paid attention to shrimp but focused on fish, prawns, and crabs. Now that the market favors shrimp and it doesn’t require much investment, some people have turned the secondary product into the main product.

Called farming, but the shrimps are born from the water source and not released. Therefore, the pond owner only needs to maintain a suitable environment, with plenty of algae for them to hide in and release organic fertilizers such as composted chicken manure and pig manure to create algae for the shrimps to eat. Shrimp farming requires a clean environment, so it can be said that this is an ecological model, organic and environmentally friendly.

Every day, Mr. Nhanh collects shrimp by using a bagua or a small net. In the peak season, he can catch more than 10kg, and normally, he can catch 7-8kg. In the past, shrimp was food for the poor. When he caught a lot, he would dry it and store it for later consumption. But now, he sells it on the spot for 140,000 VND per kg, and prepares it into many dishes such as salad with rice paper, stir-fried with lemon leaves and scallion oil...

Shrimp farming requires clean water. Shrimps this big already have eggs. Photo: Duong Dinh Tuong.

In years with good weather and little rain, shrimps grow well, meaning a lot of yield, but this year with a lot of rain, shrimps grow less. Shrimps' natural enemies are fish, but Mr. Nhanh does not filter them out but lets them fight biologically. With more than 1 hectare of pond, Mr. Nhanh earns about 250 - 300 million VND each year and only spends a few million VND on buying chicken manure and pig manure to compost organic microbial fertilizer to grow algae for shrimps. The profit margin can be said to be the highest among current aquaculture subjects.

The pioneer of the shrimp farming model in the region is Mr. Vu Van Doan. He has now transferred the pond to his son, An, to manage. For the past 2 years, Mr. An has devoted 3 hectares to the shrimp farming model.

“When my father raised freshwater fish, shrimp were abundant, but when I switched to saltwater, they all died. Two years ago, I switched to freshwater and bought shrimp breeds to raise. Every month, I harvest 15 days and don’t harvest 15 days so they can reproduce. Each time, I get about 30kg, so I earn 500-600 million VND per year. I am breeding shrimp on the remaining 20 hectares, because there are many low-value tilapia, so I have to remove them all so they don’t eat the shrimp, leaving only high-value sea bass.

During the process of raising shrimp, I saw that they also got sick, the most dangerous was red body disease transmitted from shrimp, there was no way to cure it, just let them die on their own but they won't all die, the remaining ones will continue to reproduce", said Mr. An.

Ms. Nguyen Thi Huyen Thu - Deputy Head of Tien Lang Agricultural Extension Station said that the shrimp farming model has the potential to develop on a large scale if people understand their biological characteristics. Currently, the district has thousands of hectares of freshwater ponds and lagoons, plus thousands of hectares of brackish water ponds and lagoons that are completely suitable for shrimp farming.

In addition, in the fields, the low-lying land area where rice is grown can be combined with shrimp farming if it is cultivated in an organic direction, without using pesticides to kill golden apple snails, herbicides, pesticides and not overusing chemical fertilizers. However, currently no household has followed this direction.

Source: https://nongsanviet.nongnghiep.vn/tha-rong-de-nuoi-tep-lam-choi-an-that-d405832.html