Don't overthink it. Close your eyes and just listen to intuition. If you are thirsty, drink something. If you are hungry, eat something.
Don't worry about eating according to a schedule or eating a certain amount of calories. You can create problems by eating when you are not hungry. You need to give your body a break sometimes. Don't worry about getting a certain amount of protein or carbohydrates. Just trust your body to sort things out. Eat and drink to the extent your body tells you to. Just like you did as a child. There is a lot of unnecessary stress created over this. If these simple principles aren't working along with consuming the other appropriate foods, then you may want to experiment with Cytomel. That helped me with fluid issues.