Concentrated microalgae belonging to the diatoms group of the genus Thalassiosira. Large marine microalgae (20-30 µm) with high concentrations of lipids and carbohydrates, B vitamins, carotenoids and chlorophyll. Suitable for the nourishment of larvae and post larvae of crustaceans, as maintenance diet for copepods and Artemia; and as nourishment for the nursery phase of shellfish seed (oysters, clams, mussels, scallops, etc.) exceeding 150 microns and during the conditioning of shellfish broodstock. Produced and packed in hygienic conditions, it ensures a complete nutrition, enhancing growth and the vitality of the cultivar. Allows for the reduction in operational costs by diminishing on-site microalgae production requirements, making year-round larval production feasible.