This fresh AND saltwater formula is labeled for “aufwuchs” eaters. Aufwuchs is a combination of green algae, diatoms, and small plants, along with tiny organisms such as insect larvae, crustaceans, rotifers, protozoans, and snails that live with them on the surface of hard substrates such as rocks. Many species of fish such as Mbuna cichlids, various plecos and gobies are specialized to feed on aufwuchs by scraping hard surfaces for whatever nutrients they can find. These species do eat a lot of low-caloric algae, but it is the small meaty treats that they relish and what really makes them grow and thrive. Soilent Green is a no-expense-spared blend of algae (25% of formula), combined with the highest quality whole aquatic animal ingredients, to provide a perfect balance of plant and aquatic animal proteins. Soilent Green is perfect for more herbivorous fish, shrimps, crabs, and snails.