Aeration is the process of introducing air into water in order to increase oxygen saturation. Oxygen is essential for the survival of fish and other aquatic inhabitants. It’s also a vital component in maintaining water quality as it is used by aerobic bacteria to eliminate organic pollutants from water.
In nature, aquatic habitats such as lakes, oceans, and rivers have large surface areas. The surface tension is broken by the continuous motion of currents, wind, and weather. This allows the natural exchange of gases where oxygen penetrates and dissolves in the water and carbon dioxide produced by the aquatic inhabitants is released into the air. Since an aquarium is a closed system, these natural processes need to be duplicated artificially.
In short, proper aeration helps keep aquarium fish healthy.
DID YOU KNOW?
Surface area limits the stocking capacity of an aquarium. Tall aquariums as well as irregularly shaped ones, such as a hexagon tank, can have fairly small surface areas, thus reducing the tank’s ability to allow proper gas exchange. Additional aeration is generally recommended for these types of freshwater aquariums.
FACTORS AFFECTING OXYGEN CONTENT IN AN AQUARIUM:
The amount of oxygen water can hold decreases as the water temperature increases. Warmer water is less capable of retaining oxygen so there is a greater need for aeration in aquariums with temperatures greater than 80ø F (26.6ø C).
NUMBER OF FISH:
The higher the number of fish in the aquarium, the greater the demand for oxygen.
WATER QUALITY (AMOUNT OF ORGANIC WASTE):
Oxygen is a vital part of the aquarium’s Nitrogen Cycle. It’s used by bacteria that naturally break down organic waste. To maintain proper biological filtration, an aquarium with a high amount of organic waste materials (i.e.: a tank where fish are overfeed) will typically require more oxygen.
Saltwater does not hold as much oxygen as freshwater. To provide adequate oxygen, create a water surface overflow and use an adequate circulation pump.
DID YOU KNOW?
Aquariums with solid covers or closed-fitted canopies are candidates for stagnant air, low oxygen levels and high levels of carbon dioxide. Aeration equipment helps eliminate this problem.
TYPES OF AQUARIUM AERATION:
One of the main methods of providing aeration is to use an aquarium filter. Clip-on filters, for example, break surface tension when the filtered water is returned to the tank. However, a filter may not circulate the water in the corners or at the bottom of the aquarium. Powerheads, water pumps and protein skimmers are all effective ways of creating circulation.
Additionally, air stones create bubbles that circulate water enough to help mix and distribute minerals and compounds in the aquarium. These bubbles also break the water surface tension. This enables proper gas exchange. Air stones are an inexpensive way to aerate your aquarium.
DID YOU KNOW?
It’s not actually the bubbles in air stones that provide oxygen to aquarium water, it’s their ability to agitate the water surface and provide circulation that helps raise the concentration of oxygen in the tank.
NOTES OF CAUTION:
It’s possible to have too much circulation. If fish are struggling in the current, you need to reduce the circulation in the aquarium. The amount of water movement fish can tolerate varies by species.
If the aquarium has live plants, create a gentle surface movement to reduce carbon dioxide loss (carbon dioxide is a key element in the photosynthesis process of plants).