Algae are increasingly being used in aquaculture due to their environmental benefits, cost-effectiveness, and ability to enhance the health and productivity of aquatic species. This review highlights the diverse applications of algae in aquaculture, including their use as feed supplements, water quality improvement, and disease resistance enhancement. Algae, particularly microalgae, are rich in nutrients and can replace fish meal and fish oil in aquaculture feeds, reducing reliance on marine resources and promoting sustainable practices. Algae contribute to improving water quality by removing excess nutrients and pollutants, and they serve as valuable feed components that enhance the growth performance, immune system, and disease resistance of aquatic animals. Algae-based feed supplements have shown significant benefits in improving the health and productivity of various aquatic species, including fish and shrimp. Additionally, algae-derived compounds such as astaxanthin and polysaccharides have immunostimulant and antimicrobial properties, further supporting the health of aquatic animals. The integration of algae in aquaculture systems not only supports sustainable practices but also helps in reducing the environmental impact of aquaculture. Algae cultivation is also effective in wastewater treatment, contributing to the circular bioeconomy in aquaculture. The review emphasizes the potential of algae in promoting sustainable aquaculture by enhancing water quality, improving feed efficiency, and supporting the health of aquatic species. Regulatory considerations are also discussed, highlighting the importance of compliance with safety and environmental standards in the use of algae in aquaculture. Overall, the use of algae in aquaculture represents a promising approach to achieving sustainable and environmentally friendly aquaculture practices.Algae are increasingly being used in aquaculture due to their environmental benefits, cost-effectiveness, and ability to enhance the health and productivity of aquatic species. This review highlights the diverse applications of algae in aquaculture, including their use as feed supplements, water quality improvement, and disease resistance enhancement. Algae, particularly microalgae, are rich in nutrients and can replace fish meal and fish oil in aquaculture feeds, reducing reliance on marine resources and promoting sustainable practices. Algae contribute to improving water quality by removing excess nutrients and pollutants, and they serve as valuable feed components that enhance the growth performance, immune system, and disease resistance of aquatic animals. Algae-based feed supplements have shown significant benefits in improving the health and productivity of various aquatic species, including fish and shrimp. Additionally, algae-derived compounds such as astaxanthin and polysaccharides have immunostimulant and antimicrobial properties, further supporting the health of aquatic animals. The integration of algae in aquaculture systems not only supports sustainable practices but also helps in reducing the environmental impact of aquaculture. Algae cultivation is also effective in wastewater treatment, contributing to the circular bioeconomy in aquaculture. The review emphasizes the potential of algae in promoting sustainable aquaculture by enhancing water quality, improving feed efficiency, and supporting the health of aquatic species. Regulatory considerations are also discussed, highlighting the importance of compliance with safety and environmental standards in the use of algae in aquaculture. Overall, the use of algae in aquaculture represents a promising approach to achieving sustainable and environmentally friendly aquaculture practices.