Complex sentence: Most species in this family occur on rocks or coral reefs in shallow waters of tropical oceans, including the Indo-Pacific, the Caribbean Sea, and other marginal warm seas, but they are also found in the Atlantic Ocean and the Mediterranean Sea.
Split into simpler sentences: Most species in this family occur on rocks or coral reefs in shallow waters of tropical oceans, including the Indo-Pacific, the Caribbean Sea and other marginal warm seas. But they are also found in the Atlantic Ocean and the Mediterranean Sea.