Re: length of Master-Cleanse - my minimum is 10; I've done two 10-day, one 12-day, one 14-day, and one 21-day. I'm not sure how long this one will be other than at least 10 days.
Re: white tongue - I don't know if it is normal to not have one; it does seem that most people get the white coating, but I have read of a few people who don't. This time around my tongue is barely coated, but I don't believe it is because I'm not toxic. I really don't know, the body reacts in different ways. Usually my skin on my face clears up during a MC, this time around it is all splotchy and rough looking (on day 7, anyway) and I have a big zit on my left cheek! Yuck!