Embodiments of the present disclosure pertain to compositions that include: (1) a microalgal co-product； and (2) microalgae whole cells. In some embodiments, the microalgal co-product is derived from Nannochloropsis sp., and the microalgae whole cells include Schizochytrium sp. In some embodiments, the compositions of the present disclosure are completely free of fish oil and fishmeal. Additional embodiments of the present disclosure pertain to methods of cultivating aquatic species by applying the compositions of the present disclosure to a water source that contains the aquatic species. The methods of the present disclosure may be utilized to cultivate numerous aquatic species (e.g., freshwater tilapia) and improve various metabolic parameters in the aquatic species.
