Had one small kidney stone, that was enough of a wakeup to stop drinking so much processed nonsense and add more water. I do tend to add the flavored sugar free water mixes though, rather than plain water, but it's the cutting of the Mt. Dew and such that's helped. I do drink a fair amount of coffee (3-4 cups a day), followed by a half gallon or more of water before I leave work, then more at home. I never heard the half of your weight rule, but I'm right at or slightly over that per day.