I just completed my OW and I'm also a chain vaper, during my training I consumed a 12l tank on an average of 30 min dive, after some consideration with my instructor we figured it must be because I'm a vaper. Because when I dive I tend to breath like I was vaping so frequent deep breaths, full lungs and complete emptying them, this not only make me use a lot of gas tank but also make my Hovering a mess, so I would like to ask you if you guys capers/divers have any experience or advice?