I find Miffy doesnt really drink if shes had plenty of greens, you shouldnt give her lettuce it has hardly any vitamins in it and can give them the shits. you should try to feed her at least 4 different bits of veg a day (have a look at the sticky posts at the top of the rabbit forum theres a big list of good foods) and only feed carrots and apple etc as treats as there very high in sugar.