First, it is important to get the fears of fasting and hurting your body out of your mind. We hurt our body by eating bad foods but do not have fear at all to take slow poison, why is that?
Your body is designed to take care of itself when allowed it the time to heal.
For Epsom Salt and Potassium Chloride bath start with 1 cup to full bath then you can double it after a few baths. Minimum of one bath per day is helpful. If bath is time consuming you can do the footsoaks with ES or PC.
The sign to stop the fast is when the real hunger returns, usually after 30 plus days. Clean bodies take shorter time to get to that stage. Drink water as per thirst, yes, there is something called drowning yourself by drinking too much water.
Also if you vomit for three days or have severe chest pain, I would stop the fast with freshly squeezed organic orange juice.
Once again if you have fears, start with freshly squeezed juice fasting and ease into water fasting.