I give Lelani the waterbottel, she takes two sips and then gives me a what-the-hell face!! Seriously, I would only give water when it is very hot (summertime) or if she is constepated. And then just as much as she would drink. You don't need to force him. I put 50ml in a bottel and like I said, two sips at a time between feeds. No need otherwise, you make the formula with water.