Dude your are talking about very sensitive tests,
The only way to make sure you are going to pass a test 100% is to not smoke....it's not the end of the world if you don't smoke for a couple of weeks.

How are you going to sneak water in there??...surly they would say leave your water outside as it has been tried 1000 times before.

I'm just curious as I have seen this type of thing posted alot here before and people have suggested different formulas...cranberry juice and some chemicals that claim to clear your system in 24 hours.....but I don't think these are certain ways to sort it out.

Sorry I couldn't be much help i'm just interested in how this works.

Best of luck


Edit: I don't know much about testsas it doesn't happen here....but sneaking someone elses piss in sounds like a good idea!
again good luck