No toxic fertilizers or insecticides are allowed inside Biosphere 2 and a large population of crazy ants developed. Among other problems, the ants clog sensors and electrical outlets inside Biosphere 2. It is a self-sustaining system, controlled by technology, and driven by energy from the sun. Pumps circulate water and a wave machine keeps water moving around the coral reef. Salinity, temperatures, and pH levels are controlled.
Algae scrubbers control the nutrient and oxygen levels.
The Biosphere 2 ocean is a unique area for ocean research. There are many fish such as file fish, sergeant majors, damsel fish, parrot fish, and huge angelfish but no predators such as sharks. The Biosphere 2 Rain Forest has many of the same characteristics as rain forests on Earth. Rain forests provide oxygen as well as foods, fibers and medicines. Researchers selected 300 species of plants to be placed inside the rain forest.