Adding air to your tanks can help manage pH and create a gentle current within your tanks. Typically, air is added through a pump with an in-line air filter and dispersed in the tank via an airstone. These pumps can be found in small, medium, and large sizes.

The goal is to have air bubbles gently creating water movement within each tank while avoiding a lot of turbulence around your spools. To help manage the strength of aeration, add in air manifolds so you can adjust the air levels within each tank. Take a quick look at the tanks each day, and adjust the level of aeration via the manifolds as needed. 

If you already have enough water flow within your tank from your circulation system—especially if water is being introduced from above—you may not need aeration.