What is the difference between compressed air and CO2?
When considering a gas source for your paintball marker, there are two types to choose from: compressed air and CO2. CO2 is the most widely used gas for paintball markers. CO2 tanks are cheaper than compressed air tanks and are available in a variety of sizes from 4 to 24 ounces. Many sports supply stores and most all paintball fields are capable of filling CO2 tanks and generally charge by the ounce to fill them. Compressed air tanks are more expensive than CO2 tanks and can only be filled by fields and paintball specific shops. They do however provide a significant performance increase for your paintball marker. Compressed air provides a more consistent gas source and will not freeze internal seals like CO2 under higher rates of fire.
Which should I purchase?
There are a few main points to consider when choosing between compressed air and CO2. One of the most important factors to consider is the type of marker you will be using. Higher-end brands such as DLX, Dye, Eclipse, Bob Long, DP, and Empire strongly recommend compressed air as a gas source for their electronic markers. These markers many times are not compatible with CO2 and can be damaged if CO2 is used resulting in expensive repairs. Mechanical, blowback and most milsim style markers from companies such as BT, Tippmann, and GOG are capable of using CO2 or compressed air as a gas source.
The second factor to consider is the availability of a certified fill center. CO2 is more widely available than compressed air in most locations. If you frequently play paintball at an established field, many times it is cheaper in the long run to purchase a compressed air tank, as fills are usually free. If you play paintball in the woods with your friends and are far from an established field, CO2 is recommended as a gas source.