Hi Joules, besides the diet drinks and Crystal Light, you can squeeze half a lemon or lime into your water. We've been doing that in our house for a few years now, and even in restaurants we order water with lemon. It makes the water tasty and if you don't want to have a lot of artificial sweeteners in your drinks, it's a good substitute. Most everything I read says 8 8-oz. glasses of water a day but I believe they don't count coffee as part of that. I know I don't drink 64 oz. of water a day but I do drink several glasses, or half glasses here and there, which might be close to 40 oz. if I measured it.