Vietnamese fisheries magazine addresses ammonia nitrogen and hydrogen sulfide control in shrimp ponds: three parallel measures of feed control, aeration and bottom cleaning

The Vietnamese fisheries magazine Thuy san Viet Nam published a technical Q&A on 12 November 2026 responding to a question raised by farmer Phạm Đình Chương in Núi Thành commune, Da Nang city: how to limit toxic gases such as ammonia nitrogen (NH₃) and hydrogen sulfide (H₂S) in shrimp ponds. The reply was given by the magazine's Science and Technology Department (Ban KHKT).

The reply noted that NH₃ and H₂S are usually produced during the decomposition of leftover feed, excrement and bottom sediment, and are particularly evident when the pond has a high organic load and low dissolved oxygen, so water quality needs to be controlled well from the start of the farming season.

On feeding, the reply advised farmers to feed reasonably and avoid excess feed, and to regularly test indicators such as pH, dissolved oxygen, NH₃ and H₂S so that adjustments can be made in time. Maintaining stable dissolved oxygen, especially at night and in the early morning, helps limit the conditions for H₂S formation.

On pond organic matter management, the reply proposed dealing with it through siphoning, collecting waste and controlling bottom sediment, and said suitable biological products can be used to help break down organic matter, but products of clear origin must be chosen and used according to regulations.

For NH₃, the reply listed maintaining an appropriate pH level, limiting pH fluctuations within a day and controlling the amount of feed as important measures. When toxic gases rise, the cause needs to be identified and addressed item by item, rather than focusing only on water exchange.

On the day the Q&A was published, the same section also listed similar technical articles including "Prevention and treatment of water mold when the weather turns cold" published on 8 November and "Solving the problems of weak swimming and crowding in corners in cage fish farming" published on 7 November.