Many homeowners have recently been embracing the incorporation of aquascapes of various sorts into their landscapes. These often include ponds, which provide valuable ecosystems for aquatic plants and critters, in addition to bringing incredible amounts of peace and happiness to human residents and visitors alike. However, to keep these elaborate ecosystems living water aeration is absolutely necessary.
Generally speaking, any procedure that adds oxygen to a body of water is considered water aeration. This added oxygen is what allows plants and animals to survive. In nature, this is accomplished through sub-surface and surface aeration, typically provided by aquatic plants or natural streams, waterfalls, or even wind movement. Those who wish to install man-made ponds are unlikely to have enough surface area for these natural processes to come into play. There are, however, a number of different ways to accomplish this goal using machinery as well.
Fountains, floating surface aerators, and paddle-wheel aerators all fall under this broader category. Fountains can be a very visually appealing way to provide oxygen, but they are not efficient enough at it to support plant life or aquatic animals. Surface aerators work in a similar way, by using impeller pumps to extract water from the surface of the pond and transfer oxygen into it using air-water contact. They are typically powered with on-shore electricity, and provide a practical solution to aerating backyard ponds.
This broad category describes aeration techniques that release bubbles at the bottom of the pond or other body of water, which both aerate and mix the water as they rise to the surface. Coarse bubble aeration systems work by pumping air into the pond from an on-shore compressor. A hose is attached to it, and placed at the bottom of the body of water. The release of bubbles leads to quite turbulent water displacement, and is not terribly efficient.
In comparison, fine bubble aeration is much more efficient. The mechanisms used are very similar, but a diffuser is added to the end of the hose that is placed beneath the surface of the water. This causes the air bubbles to me much smaller, giving them much more surface area, and increasing their effectiveness at transferring oxygen into the surrounding water.