An air bubbler, sometimes also called an aerator, is a device that can come in several different sizes and functions, with a few different potential applications, but typically is intended to better regulate oxygen levels in a body of water. These can be a small air bubbler used in a fish tank or small aquarium, or larger models intended for use in larger bodies of water such as small lakes and ponds. Regardless of the design or function of an air bubbler, it is usually designed to maintain a more even level of oxygenation throughout the water.
Large bodies of water, such as small lakes and ponds, can require an air bubbler for proper aeration and maintaining oxygen levels throughout the water. In standing water, there can be a tendency for the upper parts of the water to have higher oxygen content than the lower water regions. Striation can occur with the upper regions being warmer and more oxygen rich, while the lower regions are cold and oxygen deprived. These low regions may not have enough oxygen for fish to survive, pushing the fish upward and creating crowding or unsustainable environments for the fish.
This type of striation can also cause a build-up and release of various toxic gases such as hydrogen sulfide, as organic material begins to break down more slowly in an anaerobic, or oxygen-deprived, environment. An air bubbler works by moving the water around through either surface aeration or bottom aeration, to increase oxygen levels throughout the water and create a more stable environment for fish and other organic growth. For shallow bodies of water, surface aerators are typically sufficient and usually float on top of the water. They function by pulling water up into the unit, then spraying the water through the air, increasing oxygen levels in the water as the droplets splash back down.
Deeper bodies of water, those averaging more than six feet (about two meters) in depth, typically require bottom aerators installed at the floor of the pond or lake. These function by sending bubbles up through the water, turning the water over and creating a cycle of movement in the water that stirs up the upper and lower layers to maintain even oxygenation. The movement of air through the water is similar to the process of convection found in a pot of boiling water.
For smaller water systems, such as a fish tank or small aquarium, a small air bubbler is often used to better ensure proper aeration of the water. Fish require certain levels of oxygen in water to breathe and survive. A fish tank can sometimes not provide enough oxygen throughout the entire system of water, and so aeration helps to provide more regulated oxygen levels in the tank.