Feeding Fish, Corals, and Inverts:
Most saltwater fish should be fed twice per day. The best way to determine how much is by looking at your fish. If their bellies are plump, you are feeding enough. If you see uneaten food sitting on the bottom, you are over-feeding. If their bellies are at all concave, either they are not eating well, or you should feed them more. Many invertebrates will scavenge your aquarium eating scraps of food left over by your fish. Some will catch plankton and other free-floating foods out of the water. Most corals feed on different types of plankton such as photoplankton or zooplankton. Some corals and all anemones will eat a small piece of marine flesh such as squid or shrimp if you place it on them.