important for circulating air, but also for preventing the growth of mold and development and spread of harmful bacteria. This is especially important in warm, humid vivariums. The traditional method consists of placing a suction fan (or ventilation slits) at a low level and another exhaust fan at a higher level, which allows the continual circulation of fresh air. Gallery See also Aquascaping Biome Biosphere Closed ecological system Ecosphere Ecosystem Wardian case Winogradsky column Ex situ conservation Botanical garden Barn Stable Greenhouse References Pet equipment Buildings and structures used to confine animals Insect rearing