Direct Aquarium

Air Pumps and Air Stones:

Air pumps can provide vital water circulation needed to keep the dissolved oxygen content in your water consistent and evenly distributed throughout your aquarium. Whether or not bursting bubble at the water’s surface help increase dissolved oxygen, it is agreed upon that the amount of surface area on top of the water is the main factor in oxygen exchange.  Air bubbles can agitate the water’s surface as well. Agitated surface water has a larger surface area than stagnant still water because the peaks and valleys of the water increase the surface area. In short air pumps are a cheap easy way to move tank water vertically and increase oxygen exchange. And you can use air pumps to power a lot of cool decorations, and the bubbles just look cool in themselves.
Air pumps can be used to operate some types of filters such as underground gravel filters and foam filters. Some protein skimmers can also operate with an air pump.

The most popular air pump is the Tom Aquarium Products aqua lifter. This great pump can pump both air and water at approximately 3pgh. The Aqualifter is a great solution for auto top off systems because if your external backup water container runs out of water the pump will not burn up because it is also made to pump air, unlike traditional watre pumps.