The way Corals grow on the ocean floor makes us think of them as plants, but they are invertebrates. These colorful creatures are under the class Anthozoa and depend on one another and prefer warm shallow waters or cold ocean floors. They live and grow together, forming large colonial colonies called coral polyps. These polyps are cylindrical with a mouth at the end and a series of tentacles surrounding them, which is for stinging creatures or gathering food. Corals have a clear body. However, the beautiful coloration we see on them comes from the various algae growing in their tissues. They feed on small organisms, zooplankton, and small fish and can reproduce sexually or asexually.