The zooxanthellae then use photosynthesis to break up the food and help the coral digest it. This type of relationship is called symbiosis. The two animals, working as one animal, feed each other. Coral use the water current for many things. A good water flow brings them food, helps to clean them, and is used for reproduction.
Coral can reproduce both sexually and asexually.
Some coral will release both sperm and eggs into the water, where they join and collect on the sea surface. This will often take place during a full moon when tides are lowest. Asexual reproduction occurs when a section of coral breaks off and reattaches onto another part of the rock or sea floor. A coral reef is often made up of hard coral, soft coral, tubeworms, mollusks, and other types of animals and fish. Some fish, like the clownfish, spend most of their lives in and around coral reefs.