Oxygen is essential to all aquatic organisms, and there are many ways to oxygenate the aquarium.  Air pump The most common form of aeration in an aquarium is through an air pump. The air pump is usually located outside the aquarium and needs to be plugged into a power source. They work by vibrating a rubber diaphragm. When the diaphragm in the pump vibrates, the air is sucked in and pumped... View more