Ninh Binh: Converting low-yield rice fields to giant river prawn farms

Le Nhu Quynh from Lang Phong Commune, Nho Quan District, initially converted a low-yield rice field into a freshwater fish pond in 2021 but found the returns modest. In 2023, he transitioned to farming giant freshwater prawns and achieved immediate success with his first harvest.

In 2024, he expanded the farm to 1 hectare, embracing organic practices by using locally sourced feeds, such as maize, rice, and bycatch fish, as an alternative to commercial feeds. He also developed additional ponds and introduced marble goby for trial.

Quynh noted that giant river prawn farming on former rice land yielded significantly higher economic returns. The organic method further enhanced these results, with the prawns growing robustly, exhibiting few diseases, and keeping labor and costs in check.

On his 1-hectare farm, Quynh now averages 2 tons of prawns per harvest, fetching 180,000-250,000 VND per kilogram and generating around 400 million VND per cycle. After expenses, including feed, labor, and electricity, his profits average about 300 million VND.

Strict pond management is essential to maintain quality. Quynh treats his ponds with lime to sanitize and balance pH before introducing prawns. The water is filtered through a sedimentation pond to curb pathogens, while pond levels are maintained at 1.5-1.7 meters. Water changes occur one to two times per month to keep the pond clean, and high-quality prawn stock is sourced to minimize loss from predators and disease.

To avoid issues during seasonal changes, when oxygen levels drop, he maintains aeration and monitors pond conditions closely, particularly at night when prawn suffocation is a risk. Continuous aeration and vigilant monitoring help mitigate these risks.

With earthen ponds, giant river prawn should be stocked in late February in the lunar calendar and harvested around October or early November, avoiding cold weather and ensuring prawns meet market sizes of 10-15 per kilogram.

VFM