Recirculating systems are a type of aquaculture system in which water is continually recycled and reused within a closed-loop system. This means that the water is filtered and treated to maintain optimal water quality for the aquatic organisms being cultivated, such as fish or shrimp. Recirculating systems are designed to be highly efficient and sustainable, as they minimize water usage and waste production compared to traditional open systems. This research area focuses on developing and improving recirculating systems to maximize productivity, minimize environmental impact, and ensure the health and welfare of the aquatic organisms being raised. Key areas of research in recirculating systems include water quality management, system design and engineering, biosecurity, and sustainable production practices.