Feed efficiency in aquaculture is essential for sustainable production, as it impacts both environmental and economic outcomes. It refers to the ability of aquatic organisms to convert feed into body mass effectively, minimizing waste and reducing costs. By improving feed formulations—using alternative protein sources, plant-based ingredients, and functional additives—feed efficiency can be significantly enhanced. This not only helps aquaculture farms reduce their reliance on wild-caught fish for feed but also lowers the carbon footprint. Improved feed efficiency promotes faster growth rates, healthier fish, and overall sustainable practices, contributing to food security and reducing the environmental impacts of aquaculture.