Air sparging utilizes the same principles as packed towers. The principle design being that of an 'air to water ratio'. One major difference is that packed towers pass the water to be treated vertically down a stack utilizing gravity and surface area, created by a packed media to accomplish the proper air to water ratio, while air sparging is a method of introduced air into the liquid horizontally in either a batch tank or a flow through operation. One of the more critical aspects of air sparging is that of the method in which the air is introduced into the liquid to achieve the proper air to water ratio.