虎龙杂交斑循环水育苗系统设计及应用效果.

In order to further study the feasibility of recirculating aquaculture system in the production process of marine fish fry. Using the principle of material balance, combined with the construction technology of recirculating aquaculture water treatment facilities and equipment. The water treatment process was optimized and the key parameters such as volume and circulation of moving bed bioreactor were designed. A set of recirculating aquaculture hatchery system was constructed. Two water treatment loops were designed, and efficient water treatment technologies and equipment such as dual drain system in hatchery tank, radial flow separator and moving bed bioreactor were integrated. The experiment of hybrid grouper (Epinephelus lanceolatus♂ × E. fuscoguttatus♀) hatching was carried out by using this system, focusing on three water quality parameters of dissolved oxygen concentration (DO), pH and total ammonia nitrogen (TAN), as well as three growth parameters of total length, body weight and emergency rate. Results: The growth of larvae and juveniles was well, with an average length of (75. 1±0. 55) mm, an average body weight of (9. 2±0. 42) g, and a hatching emergence rate of 16. 28%. The water quality test results showed that the temperature was 26. 8 -27. 7℃, dissolved oxygen concentration was 6. 6 - 7. 2 mg/L, the average pH was 8. 31, and the average concentration of total ammonia nitrogen was (0. 183 ± 0. 191) mg/L, indicating good water quality. The economic analysis results show that the single crop profit is 18 600 yuan, and the annual profit is 55 800 yuan (calculated based on three crops per year), which has good economic benefits. Conclusion: This research can provide technical support for the application and popularization of recirculating aquaculture system. [ABSTRACT FROM AUTHOR]