Beer gas
 

I have two co2 tanks now, I use one to feed 3 kegs in my fridge and the second to force carb. My uncle is giving me his tap system with a co2 tank. I would like to get the third tank filled with nitrogen or beer gas (are they the same thing?) to pour a stout so I stopped at the place I get co2 and asked them about it. They told me the regulator's are different and I would need an adapter. Is this true??

Beer gas is a mix of Nitrogen and CO2. Yes it is true, you'll either need an adapter to use your existing regularor, or a new regulator for beer gas.