Well some people complained that there air stones got plugged after a while using CO2 a white deposit, so someone said to run your main line into a 20 ounce bottle, and from the 20 ounc bottle to the air stone.
I ran my straight for a while, i can post a pic after a while when its time to do water change on my tank, I didnt use the 20 ounce bottle right away since i had an air leak in the cap and i have alot of white residue on the stone.