what  do fish eat?
 Most of the ocean fish usually eat each other, as well as crustaceans such as shrimp, krill and crabs. Ocean fish also eat kelp, algae, detritus and plankton, as well as cephalopods such as squid and octopus and also echinoderms such as sea urchins. Some ocean fish are scavengers and feed on the carcasses of other marine animals. 