The key role and application of dissolved oxygen in aquaculture

Dissolved oxygen (DO) refers to oxygen dissolved in a molecular state in water and is one of the most important environmental factors in aquaculture. For aquatic animals such as fish and shrimp, sufficient dissolved oxygen is necessary to maintain normal growth and metabolism. However, in closed or semi-closed aquaculture environments, poor water mobility, dense stocking density and decomposition of organic matter in the water often lead to a decrease in dissolved oxygen levels, which in turn affects the health and yield of farmed animals. Therefore, in the process of aquaculture, monitoring and managing dissolved oxygen has become the key to improving production efficiency and ensuring the success of aquaculture.

In a shrimp farm in a coastal area, the main species is white shrimp. The farm adopts traditional pond farming methods with a high stocking density. The pond water contains a large amount of organic matter, such as feed residues and shrimp excrement. Initially, farmers relied on traditional manual experience to judge water quality and did not use special equipment to monitor dissolved oxygen content. As the scale of farming expanded, shrimps often experienced stress reactions and even large-scale deaths, causing serious economic losses.

In order to solve these problems, the farm introduced modern water quality monitoring equipment, including dissolved oxygen sensors and automatic aerators. By real-time monitoring of dissolved oxygen in water, the farm can keep track of the oxygen content in the water at any time. When the dissolved oxygen level is lower than the preset value, the automatic aeration system will start immediately to ensure that the oxygen supply in the water is sufficient. At the same time, combined with the water circulation system, the farm effectively reduces the accumulation of organic matter in the water and improves the overall water quality.

By introducing the dissolved oxygen monitoring system, the farm has achieved remarkable results:

1. Reduce stress response and mortality: After continuous monitoring and regulation of dissolved oxygen levels, the growth environment of shrimp has been significantly improved, stress response has been significantly reduced, and mortality has dropped from the original 10% to less than 2%.

2. Improve production efficiency: Under a stable dissolved oxygen environment, the metabolism and feeding capacity of shrimp are improved, the breeding cycle is shortened by about 10%, and the overall output is increased by 15%.

3. Save costs: Compared with traditional artificial aeration, the automated system not only reduces the number of manual interventions, but also saves energy. The aerator is only started when needed, which greatly reduces energy waste and reduces operating costs.

Based on the above, we can draw some inspiration and summarize the following points:
(1) The importance of scientific monitoring: Real-time monitoring of dissolved oxygen content is one of the key factors for the success of aquaculture. Through the automation system, farmers can accurately grasp the water conditions and respond in time, avoiding catastrophic losses caused by insufficient oxygen.
(2) Ecological balance management: In addition to the management of dissolved oxygen, the balance of the ecosystem in the aquaculture water is equally important. Through reasonable water circulation and organic matter treatment, the utilization of dissolved oxygen can be further optimized and the risk of water quality deterioration can be reduced.
(3) Return on technology investment: Although the installation of monitoring systems and automatic aeration equipment requires a certain amount of capital investment in the initial stage, in the long run, the automated management system not only improves the aquaculture efficiency, but also significantly reduces the operating costs, with good economic benefits.