My morning was already rough to begin with due to a migraine. Other than that I'm fine. If you are already planning to mix juice and Water Fasting adding fresh lemon or lime is fine. I can't stand plain water either so every time I do a Water Fast I struggle myself. When I start to get the grumbles I drink some more water (it kinds of fools the stomache for a while.) after a few days the grumbles stop. Keep reminding yourself why you are fasting it will help keep you focused when things start to get rough. Keep on fasting, you are doing great.