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In order to explore the feasibility and application development value of simple, stable and low-cost recirculating water aquaculture system, a freshwater fish recirculating water aquaculture system was constructed by optimizing and improving the water intake structure, oxygenation mode and streamlining the system composition, and a 90 d largemouth bass aquaculture trial was carried out to verify the system indexes. The results showed that at the start-up stage, the biofilm could be successfully hung in 18 d with a mixed culture in the mode of 2∶3 ratio of mature filter media to initial filter media;during the culture process, the mean values of temperature, dissolved oxygen concentration and pH were (27.60±0.30)℃, (10.25±0.23) mg/L and 7.10±0.31, respectively, and the mean values of ammonia nitrogen concentration and nitrite nitrogen concentration were (0.27±0.14) mg/L and (0.10±0.03) mg/L, nitrate nitrogen concentration range was between 7.41 mg/L and 35.89 mg/L, and water turbidity was (0.25±0.01)NTU (nephelometric turbidity units);the average mass of largemouth bass was increased from (61.25±3.06) g to (256.54±12.84) g, and the maximal culture density reached 42.54 kg/m3, with a mean bait coefficient of 1.16 and a survival rate of 98.85%~100%;muscle texture characterization revealed that the muscle hardness of largemouth bass was increased moderately and elasticity was increased, which enhanced the taste of the fish;the running cost was about 21.16 yuan/kg, which could yield a good economic return. The research result was conducive to the popularization of recirculating water aquaculture system and it can provide a reliable platform for freshwater fish scientific research.