Assessment of water prophylaxis and biosafety in finfish aquaculture - current and emerging technologies.

Effective water quality management is a fundamental component of disease prevention, fish welfare, and sustainable production in finfish aquaculture. As aquaculture continues to expand to meet increasing global food demand, maintaining biosafe aquatic environments has become increasingly challenging due to production intensification, climate change, emerging pathogens, and the spread of antimicrobial resistance. While conventional approaches such as mechanical filtration, biofiltration, ultraviolet disinfection, ozonation, and water exchange remain central to water prophylaxis, increasing attention is being directed toward technologies that support earlier pathogen detection, improved risk assessment, and more targeted intervention strategies. This review examines water prophylaxis and biosafety through an integrated framework that links water quality, microbial ecology, pathogen surveillance, antimicrobial resistance, and preventive interventions. First, the biological and environmental mechanisms through which water quality influences disease susceptibility, microbiome stability, pathogen persistence, and antimicrobial resistance are evaluated. Conventional water-treatment technologies are then assessed alongside emerging approaches, including environmental DNA/environmental RNA monitoring, probiotics, phage therapy, biosensors, smart sensors, microfluidic platforms, and droplet-based molecular diagnostics. Emphasis is placed on their practical applicability, technological readiness, and suitability for different finfish production systems. The review highlights that effective biosafety management depends increasingly on integrating environmental monitoring with molecular diagnostics, risk assessment, and targeted interventions rather than relying solely on water-quality control or reactive disease treatment. Emerging technologies differ substantially in readiness, ranging from established and pilot-stage approaches to experimental technologies that require further validation before routine implementation. To support practical decision-making, the review synthesizes these technologies within an integrated water-prophylaxis and biosafety framework that links monitoring, diagnostics, risk assessment, intervention strategies, and reassessment pathways. Overall, sustainable finfish aquaculture will depend on combining conventional water-treatment infrastructure with advanced surveillance technologies and preventive biological interventions within coordinated biosafety programs. Such integration offers considerable potential to improve fish health, reduce environmental impacts, support responsible antimicrobial use, and enhance the long-term resilience of aquaculture production systems.