There is a product that comes in packets called True Lemon and True Lime. They are sized like a sugar packet for coffee. I throw one of those in my 24 oz water bottle and drink my water like that- slightly tart and very refreshing.
If I am dying for something sweeter, I put 2 or 3 drops of flavored Stevia liqud (Chocolate Raspberry, Vanilla, Apricot Mango, Mint) in my water. You can also float a teabag (like Celestial Seasonings) in your water bottle and you get a bit of flavor- it doesn't really steep in the cold water fast enough to become tea. I might refill thae bottle 3 or 4 times before I use a new bag.
My doctor told me to drink about 1/2 of my body weight in oz of water each day. That 8-8oz glasses thing is based on a 130 pound woman. But that includes the natural water in fruits, veggies, coffee, teas., broths and other drinks. I don't usually make that- I am a large woman- but some days I come close.
MY doctor is very much against artificial sweetners.
I just want to live happily ever after-every now and then. Jimmy Buffett