Haven't increased air flow on a Protank 2, though I do have one. I do make my own coils, of course. But air flow is one of the more important parts of the more advanced RBA/RDA's. Vapor and air flow go hand in hand. I have very few devices that I haven't modified the air flow in one way or another. There are also some very good devices out there that allow for variable air flow depending on the build, such as the Trident and a number of others, where air flow control is already built in. Anyway, good luck in your modding. These skills will help you with the more advanced devices. Welcome to the forum.