The Ecosystem Filtration Method is based on the principles of ecology and is a natural filtration system that simulates the environment found in coral reefs. It does not require a Protein Skimmer or activated carbon to purify the water. It keeps the water well oxygenated through the photosynthesis of Caulerpa and entirely eliminates the need for air pumps. Caulerpa can also be harvested and used as fresh, natural food for fish. In addition, Caulerpa prevents the growth of undesired hair algae by competing for essential nutrients.