The recirculating aquaculture system is a new type of aquaculture model, which uses a series of water treatment
units to process the wastewater generated in the aquaculture pond and then recycle it. The main principle of
RAS is to integrate advanced technologies in environmental engineering, civil engineering, modern biology,
electronic information and other disciplines to remove residual bait feces, ammonia nitrogen (TAN), nitrite nitrogen
(NO2--N ) and other harmful pollutants. For the purpose of purifying the breeding environment, the process of re-entering the purified water into the breeding pond by using physical filtration, biological filtration, removal of CO2,
disinfection, oxygenation, temperature adjustment and other treatments. It can not only solve the problem of low
utilization rate of water resources, but also provide a stable, reliable, comfortable and high-quality living environment
for breeding organisms, and provide favorable conditions for high-density farming.