Video by @bertiegregory. Glassfish pulsating in a cave in the northern Red Sea, Egypt. The diversity (the number of different species) of coral reefs is mind blowing. It is estimated that whilst they only occupy 1% of the ocean floor, they are home to more than 25% of the ocean's biodiversity! Coral reefs all around the world are in trouble but why should we care? Well, aside from just being awesome, they provide so many functions that are vital to human existence including coastline storm protection, fisheries production, tourism and climate regulation. Follow @bertiegregory for more wildlife adventures!