Large red copepods, Tigriopus Califoricus (250-1700 microns), that make the perfect food for mandarin gobies and pipefish, or other finicky saltwater fish. They breed quickly and continually multiply when placed in your refugium or a separate system. Since they are able to thrive in your refugium with no threat of predators, they are constantly increasing and can continually be added to your tank for food. Copepods are most active at room temperature and can be refrigerated for prolonged use. 6 oz bottle.