i can manage just under 2 litres of water . have about 10 cups of coffee or tea..... unfortunately cant do it without milk but i do have sweetners ( well from today i do ) its never affected my ketosis,but i really struggle with water . i have the orange flavour very very dilute, and maybe a diet pop. i have a litr and half jug ( from a fybogel rep ) i try to get thru it. id rather have my teeth pulled, for me thats the biggest battle and im sure if i could drink more i would have better results.