Kent Micro Vert contains a nutritionally balanced diet for corals, sponges, anemones, gorgonians, feather dusters, clams and other fine filter feeders. It is rich in vitamins and natural minerals from spirulina and kelp. Other products have not been properly preserved and smelled rotten, or were preserved with harsh, non food grade chemicals that smell like medicated mouthwash. Who wants to put these products into their expensive and sensitive marine aquarium? Kent Micro Vert is properly preserved, with preservatives reserved for human food use. It has a long shelf life without refrigeration and will provide superior results, just smell the difference.