Aquarium Aeration

Fish need to have a lot of oxygen available for respiration. So, although most filters provide water circulation and aeration, it is a very good idea to have an external air pump moving air through one or more airstones in the tank. This is especially true for tanks that are at their fullest carrying capacity. The air pump increases circulation in the tank, promotes oxygen exchange at the surface, and increases the escape of carbon dioxide, carbon monoxide, and free ammonia from the tank. This increase in circulation also acts to mix all the aquarium levels so that a uniform temperature is maintained throughout the tank.