To be honest...smoking .5 every 8 weeks with your body weight...drinking water and some cranberry here and there...I'd say you'd be clean in 5 days after smoking. You don't have a lot of fat to store thc and after 30 days mostly if not all is out of your system. Unless they do hair then your 90 days kind of fucked. So the lack of fat and how often your not smoking is going to cut the 30 days down to about a week. This is all only based off of what I have read and learned about.