Water wont help you. Your best bet is to eat lots of food, and exersize as much as you can. Drinking water WILL help if you do this, though. This technique helps replace the fat containing THC, and it burns off fat with THC in it. I highly doubt those drinks work, but many people seem to strongly believe in it. If you have a drug test, just man up and stop smoking. You dont need weed to survive.