Each small Ecosphere contains shrimps, (3 - 4) filtered seawater, algae, gorgonian and gravel which are all part of the working closed Ecosystem. All the surfaces act as hiding areas for the shrimp where micro-organisms can also attach themselves. The gorgonian (branch) is a non-living material and is hand cut for each individual Ecosphere. Simply provide your EcoSphere with a source of indirect natural or artificial light and enjoy! Because the living organisms within the EcoSphere utilize their resources without overpopulating or contaminating their environment, the EcoSphere requires virtually no maintenance. Ecospheres have an average life expectancy of two years, however, it's not uncommon for shrimp populations to be thriving in systems as old as 7 years. No two EcoSpheres are alike, making them truly unique gifts.