I honestly can't tell you which frequencies. I ran an overnight sweep of 200000-400000 (3 minutes each 1000) the day I got the machine and had to wake up to go to the bathroom throughout the night. Since then, I have had no problem going several times a day. My stools are not dark though, which shows me I still have work to do in this area.
Some specific frequencies have made me run to the bathroom. Ancylostoma (Hookworm) and Trichinella the most. I can't remember if it was Hulda's, Newport's, or DNA though.