What Organisms Make Up Coral Reefs?

What Organisms Make Up Coral Reefs? Many types of algae, seaweed, sponges, sediment, and even mollusks like giant clams What organisms make up coral? Most corals contain algae called zooxanthellae (pronounced zo-UH-zan-thuh-lay), which are plant-like organisms. Residing within the coral’s tissues, the microscopic algae are well protected and make use of the coral’s metabolic waste