I didn't answer the poll because it half worked for me..... in 1 situation i smoked a couple hours b4 the test after being clean(had no idea the test was coming, just bad timing) and the other time was a day after smoking heavily for about 4 days. Both tests came back dilute, meaning not positive but also that the sample had unusually high creatnine levels and was probably tampered with. The first time this happend i pulled it off as an innocnet mistake because i had just drank a lot of water that day, the 2nd time they didnt buy it.... But i'd say the water method will work most of the time, at least to casue a dilute result which if u still have credability will buy you some time.