Abstract: The invention relates to a granular fermentation-broth-based feed additive, comprising an L-amino acid selected from the group consisting of L-lysine, L-methionine, L-threonine, L-tryptophan, L-valine or mixtures of these, suitable for the preparation of feeds for animals kept in aquaculture, where the content of the L-amino acid or the mixtures thereof amount to 20% by weight of the total composition of the granular feed additive; where at least 70% by weight of the particles have a particle diameter of from >63 ?m to <300 ?m, where the biomass content amounts to ?5% by weight and where the surface of the particles is fully or partially coated with an edible oil, wherein the L-amino acid is L-lysine, is present as a sulphate salt and the molar ratio of sulphate to L-lysine amounts to at least 0.5.