Agricultural Horizons: Research, Technology and Sustainable Development Vol. 4

Biofloc technology has moved within two decades from an empirical pond-management practice to a component of intensive, low-exchange production for penaeid shrimp and warm-water finfish. The original control logic rested on a single manipulated variable, the carbon-to-nitrogen ratio of material entering the culture unit, and on the assumption that heterotrophic assimilation of ammonium would dominate nitrogen transformation. High-throughput sequencing, genome-resolved metagenomics and quantitative synthesis have since produced a more complicated picture, and a second-generation framing has emerged in which the microbial community itself is treated as the object of engineering rather than as an incidental consequence of carbon dosing. This review critically evaluates whether that framing is supported by current evidence. Literature was identified through structured searching of seven scholarly databases and indexes, supplemented by citation tracking and an intergovernmental source, covering 1999 to 14 July 2026. Four propositions were examined: that biofloc communities have a reproducible core amenable to directed manipulation; that carbon management delivers predictable gains in nitrogen and feed resource efficiency; that disease resilience arises from identifiable and controllable mechanisms; and that system-level resource efficiency extends beyond water saving. The evidence is strongest for a taxonomically recurrent, functionally versatile floc community, for partial and size-dependent nutritional contribution of flocs, and for pathogen-directed virulence attenuation under defined conditions. It is weakest for predictive control of community assembly, for long-term nitrogen closure given documented nitrate accumulation, and for energy and greenhouse-gas performance, which remain largely unquantified for biofloc units specifically. Reports of human-associated pathogens and intrinsic antimicrobial resistance in poorly managed freshwater systems indicate that resilience is conditional rather than inherent. Progress requires standardised reporting, genome-resolved rather than amplicon-only characterisation, longer trials at commercial scale, and explicit falsification tests of the engineering claim.