More than two thirds of the Earth's surface is covered by oceans. The larger part of our world is underwater and hidden to our eyes. Sunlight penetrates water, however, only twenty percent makes it to a depth of ten metres. Less than one percent of sunlight reaches the ocean at 100 metres depth. To make things more difficult, water filters the warmer side of the light spectrum earlier than blueish light waves. That?s why the deep blue is so blue. Red disappears at five metres depth, yellow light at ten metres, green light waves make it to 25 metres, then below it?s all blue. Yet, the world in the deep blue of the ocean is all but monochrome. We only know a fraction of what lies below.