Watch Alien Reefs (2012) : Full Movie Online Free Coral reefs are believed by many to have the highest biodiversity of any ecosystem on the planet. A lot of the life found here can seem very alien at first, they occupy less than 1 percent of the ocean floor but yet are home to more than 25 percent of all marine life. Warm water reefs typically come to mind when thinking of the Pacific Ocean and the Caribbean Sea, these reefs are very well known but they don’t just occur in warm waters. In this one hour special, we are brought into this alien environment and discover for ourselves a strange, hidden world that is simply abundant with life, ranging from the weird to the wonderful.