Absolutely a BAD idea. Epsom salt are a harsh laxative and are very dehydrating. Definitely NOT something to use while fasting. E Salts work in a totally different principle than the SWF. The SWF works because the ratio that it is mixed ( 2 tsp per qt H2O) is the same specific gravity as blood thus it will pass through the system without being absorbed rising the GI tract top to bottom in a gentle manner. The SWF is the same salinity as the saline solutions used in hospitals.
The SWF is not unique to the MC. It is an old Ayurvedic protocol, prolly hundreds of years old