That 30 days is a crock of shit. I'll admit some people with higher fat content in their bodies will retain thc metabolites for longer than others, but I keep smoking right up until my test every time and i've never failed one that I wasn't failing intentionally. I drink about a gallon and a half of water within 4 hours of the test and eat like 10 multivitamins to get my piss lookin real real yellow again. if you're peeing like every 15 minutes and you can't hold still and your bladder constantly hurts then you're gonna pass. that's MHO anyway. just remember to not stop drinking water, 'cuz you need to push that clean stuff out right up until you fill that little cup. oh and dont give them the beginning or end of the stream, of course