First and Only The Vault Bury talks about the various types of gas for airsoft use as well as maintaining airsoft pistols... "Today we are talking about all the Types of Green Gas you use use what What they are for.  We also Talk about Pistol Maintenance.

Green Gas - All round Gas propane gas and silicone contents internally.

Red Gas - Designed to make your gas Airsoft RIF more consistent between every shot and work far better in colder conditions. You will also achieve an increase in FPS but you must let the gas settle in your magazine first!

Black Gas - A high performance gas, designed to operate at lower temperatures (between 3c - 20c) allowing to use your weapon all year round. Using this high power mix gives an increase in FPS, GBB efficiency and a harder kick.

White Gas - specifically designed for Pistols with plastics slides or anyone who needs a lower power gas to bring down the FPS."