Epipelagic is the area of the water column extending from the surface of the water down to 700 feet. Since is the only zone that the sunlight can penetrate this is the only zone where plants reside. Consequently, this is where 90% of ocean life hangs out.
The epipelagic zone is also known as the sunlight or euphotic zone.
Enjoy this overview of marine science blogs that takes you through the ocean vertically … http://neurodojo.blogspot.com/2011/02/carnival-of-blue-45.html