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High-density mode was widely adopted in China’s aquaculture, and single manual control of the mechanical oxygenation mode was chosen. To ensure safety, an extensive over-anaerobic mode was used, but the security was still difficult to improve. Human resources and electricity were wasted. A new type of automatic oxygen enrichment model was proposed, which utilized a biofan to improve the water quality and increase oxygen in the case of an emergency. The biofan was driven by solar battery, which circulated water day and night. It not only released the harmful substances in the bottom water body, but also greatly improved the dissolved oxygen content of the whole water body through the photosynthesis of the algae in the water body. It led to a significant reduction in the impeller aerator time to oxygen. Through the comparison test, it was found that the variation of dissolved oxygen concentration in automatic control mode was less than that in single oxygenation model in 24h. By measuring and analyzing the dissolved oxygen content at 0.6m and 1.0m below the water, it can be seen that the difference of dissolved oxygen content in the upper and lower layers in automatic control mode was smaller than that in the single control mode. It was mainly because the upper and lower water bodies continued to cycle in automatic control mode. The concentration of dissolved oxygen in water was monitored by ZigBee wireless sensor network in real time. When the dissolved oxygen concentration was lower than the set lower limit, impeller aerator was automatically activated, and when it was higher than the set upper limit, impeller aerator was stopped to achieve the purpose of accurate oxygen.Incremental PID control mode was adopted.