A lack of oxygen causes many problems in aquarium fish care. Many things can cause this lack of oxygen, and aeration is one of the best solutions to a lack of oxygen. It can also be an overall useful addition to, for example, breeding setups, as young fish have a high need to oxygen-rich water.
There are many types of aeration to consider for your tank. Some can also be really loud and stressful for you and your fish, causing more harm than good.
While implementing aeration can be beneficial, it can also be unnecessary in certain cases resulting in wasted money and effort on your end.