Shrimp culture rearing systems are dynamic with numerous processes influencing system performance. This research investigated the effects of stocking density, feeding level and C:N ratio on shrimp production, water quality and microbial community composition in a biofloc shrimp rearing system, using a 3 × 3 factorial design. Pacific white shrimp (Litopenaeus vannamei) were stocked at 27, 120, or 300 individual m⁻³ and fed 100, 80 or 60% of the recommended daily feed ration. For each combination of stocking density and feeding level, C:N ratios of 7.4, 12 or 16 were created by feeding a mixture of casava and rice bran besides the daily pelleted feed input to culture tanks. After 12 weeks of culture, the harvested shrimp biomass was the highest in the rearing tanks with the highest stocking density, feeding level and C:N ratio (P < 0.05), while the individual shrimp size at harvest decreased with increasing stocking density (P < 0.05). Biofloc biomass (e.g. total suspended solids TSS, volatile suspended solids VSS) and, to a lesser degree, water quality (total ammonia nitrogen TAN, NO₂-N) were affected by ₂ and 3-way interactions of the main tested factors. The ash, protein, fat and nitrogen free extract (NFE) content in biofloc were affected by stocking density (P < 0.05), and ash and NFE content by C:N ratio (P < 0.05). Regarding the microbial community composition in the biofloc at the highest stocking density, increasing feeding level and C:N ratio led to an increasing microbial richness and diversity (P < 0.05) as a result of nutrient input. Overall, the shrimp production and biofloc biomass were influenced in a similar way by the stocking density, feeding level and C:N ratio applied in the biofloc system. Future research should focus on how the type of carbohydrates and methods of administration affect shrimp growth and biofloc formation, and how this may promote health benefits through the microbial community manipulation.

对虾养殖系统是动态的，有许多影响系统性能的过程。本研究采用 3 × 3 析因设计，研究了生物絮凝养虾系统中放养密度、投喂水平和 C:N 比对虾产量、水质和微生物群落组成的影响。太平洋白虾 ( Litopenaeus vannamei ) 的放养密度为 27、120 或 300 米⁻³并喂食推荐每日饲料定量的 100%、80% 或 60%。对于放养密度和饲喂水平的每种组合，除了每天向养殖池输入颗粒饲料外，还通过饲喂木薯和米糠的混合物来产生 7.4、12 或 16 的 C:N 比率。养殖 12 周后，放养密度、投喂水平和 C:N 比最高的养殖水槽的收获虾生物量最高（P < 0.05），而收获时的虾个体尺寸随放养密度的增加而减小（P < 0.05)。Biofloc 生物质（例如总悬浮固体 TSS、挥发性悬浮固体 VSS）和水质（总氨氮 TAN、NO ₂ -N）受₂和主要测试因素的三向交互作用。生物絮团中的灰分、蛋白质、脂肪和无氮浸出物 (NFE) 含量受饲养密度影响 (P < 0.05)，灰分和 NFE 含量受 C:N 比影响 (P < 0.05)。关于最高放养密度下生物絮团中的微生物群落组成，由于养分输入，饲养水平和 C:N 比的增加导致微生物丰富度和多样性增加 (P < 0.05)。总体而言，虾产量和生物絮团生物量以类似的方式受到生物絮团系统中应用的放养密度、投喂水平和 C:N 比的影响。未来的研究应侧重于碳水化合物的类型和给药方法如何影响虾的生长和生物絮团的形成，以及这如何通过微生物群落操纵促进健康益处。