Corals die, but reef remains. Many organisms add to reef structure including algae, molluscs, sponges and worms. Algae extremely important. While reefs can last for millions of years, the living surface is extremely fragile and easily damaged. B. Value Tourism.
Reefs are beautiful and interesting.
Bring billions each year. U.S. gets nearly 2 billion a year from reef-visiting tourists in Hawaii and Florida keys. Imagine how important to developing nations. This is sustainable. Complex ecosystem which supports species diversity.