High pressure and temperature were combined with the convenient mixture of acids to perform an effective digestion of samples from aquatic animals for phosphorus (P) analysis. Our results indicate that digestion in high-pressure bombs combined with concentrated acidic media can be a convenient way to yield all P stored in samples, and to produce accurate recoveries. Phosphorus recovery of a certified standard material (94% ± 15) and digestions of aquatic animal tissues confirmed the relevance of bomb decomposition, as well as its reliability compared to ashing and microwave oven digestion methods. Moreover, the applied digestion technique is easily manageable even in samples consisting of a few individuals. This method is relatively rapid, saves money and time, and is able to recover P from the most persistent components (e.g. bones, scales, fat) of aquatic animal tissues.