Should I place an air-stone in my tank?
• I try to avoid using air-stones in my tank because I can’t stand salt getting splashed all over the top of the tank.
• Air-stones can send millions of tiny air bubbles through the water, creating a milky effect.
• In a reef tank the air-stone may also diffuse too much carbon dioxide out of the tank which photosynthetic organisms needs to survive.
• An air-stone is beneficial if the tank has a small surface area per water volume ratio. This is because tanks that are significantly higher than they are wide often suffer from a lack of oxygen, even if water turnover is good.
• There is no need for air-stones in a reef tank or any tank with a trickle filter.

How do you increase the oxygen level in the water?
• The more water movement in a tank the more oxygenated the water.
• The more the surface water is broken the more oxygenated the water.
• The lower the temperature and salinity the more oxygenated the water.
• Photosynthetic life e.g. algae will increase the oxygen levels.
• An air pump or protein skimmer will oxygenate the water.

What are the benefits of increasing CO2?
• All photosynthetic organisms will be presented with increased chances to thrive.
• Automatic CO2 units provide pH stability.
• Symbiotic algae requires CO2.

How do you increase the carbon dioxide (CO2) level in the tank?
• The best way is to get a CO2 unit.
• The less water movement in a tank the more CO2 is in the water.
• The less the surface water is broken the more CO2 is in the water.
• The higher the temperature and salinity the more CO2 is in the water.
• Photosynthetic life e.g. algae will decrease the CO2 levels and more fish increase the CO2 levels.
• An air pump or protein skimmer will decrease CO2 in the water.

by Paul Talbot