water isn't suffice also, the ahadith states that you must consume atleast a morsel.
Karma* - that's on an ignorant tip. Do not miss out on the reward of the month of the Qu'ran.
Work hard, don't aim for an ordinary fast of abstaining from food, go above that, abstain your eyes, ears and especially tounge from haraam. The reward of good actions in ramadan cannot be expressed in words.
Don't miss your prayers, I know taraveeh is difficult but if its too hard then atleast pray your isha. Fajr shouldn't be missed, you wake up anyway and it remember, your standing infront of the creator at that time when everyone else is asleep in enjoyment.