Where Are Coral Reefs Found? Coral reefs are found in seas with warm, clear, and shallow water. These waters are often found on eastern shores of continents with oceans that have portions in the tropics. Corals that build reefs need these conditions because they need the algae to grow. The waters must be clear and shallow because the algae needs lots of sunlight to grow. This is a picture of a scuba-diver in a coral reef. Coral reefs only thrive in warm clear ocean waters.