Optimized Utilization of Organic Carbon in Aquaculture Biofloc Systems: A Review

Biofloc technology (BFT) as an efficient aquaculture alternative is attracting attention for boosting biosecurity with minimal water exchange and reduced feed intake. BFT relies on applying organic carbon to maintain a high C/N ratio above 10, which allows heterotrophs to assimilate toxic nitrogen. A high percentage of carbon loss is thus generated from BFT. For this review, a thorough search of the relevant literature was conducted to gather valuable information on the optimization of carbon utilization. The keywords searched included 'BFT', 'carbon use efficiency', 'carbon conversion', 'carbon retention', 'carbon emission', 'carbon loss', and 'carbon release'. The current review discusses the possible effects of various C/N ratios, carbon types, addition strategies, and technology integration with respect to the optimized carbon utilization in BFT. Given the extreme lack of accessible research, it was concluded that the carbon utilization in BFT is still in its initial research stage. Anyhow, this review sheds light on plausible approaches for boosted carbon utilization by adopting slow-release carbon, reducing carbon input, integrating with other technologies, and enhancing interactions between functional microbes within BFT, thereby contributing to sustainable aquaculture.