Hi, BD - I have never used Epsom Salts when I do a Liver Flush - I only use the method that Dave Frahm recommends in his book. I think the bile comes out naturally after it forces the stones out.
The Liver Flush that I use is much easier and much more gentle than the method that uses Epsom Salts . I use Epsom Salts , but not when liver flushing.
Your on day 20 of a 40 day juice fast? That is a long time. Usually fatty things like oil are avoided when juice fasting, so I would do Liver Flushing with caution and not often. I have fasted for around 20 days in the past, but I usually fast for 10 days at a time, because it takes about 1/2 as long as the fast to get back to normal eating.