Aeration is the transfer of oxygen from air into water. All healthy bodies of water need oxygen for the normal biological cycle. In large bodies of water, this occurs naturally as a result of wave action. In smaller lakes and ponds, it is easy for biological factors to become unbalanced, causing the oxygen levels to drop, making it necessary for mechanical aeration. Insufficient aeration and low oxygen levels can cause fish kills, unpleasant smells and unsightly water.

Without sufficient circulation, a pond becomes stratified with warmer water on the surface and colder, oxygen-depleted water on the bottom. Lack of oxygen increases the anaerobic (without oxygen) decomposition of the sludge at the bottom. That increases nutrients in the pond, which, in turn, increases algae blooms. An uncirculated or non aerated pond or lake develops a thermocline. This is a stratification of the water by temperature.Read more