I am new here and I Googled how to pass a piss test. I was directed to this forum and so far I have seen more people saying that Certo works. I got up this morning and smoked. I am heavy smoker too, but I am only about 105 lbs ( I hear that matters) and I got a call at about 1:30 from work wanting me to come in and take a pee test. So I mixed one packet of Certo with a glass of water and downed it. Now I am working a half gallon of water also. I have about an hour or so left before I have to go take the test. So the time elapsed between drinking the Certo and taking the test will be around 2 hours. I hope it works and I will come back tonight to say if it does or not. I just want some quick advise. Should I keep drinking water up to the test? How much? Could I have something to eat or will that screw up the test?