Hi Dave, I don't know everything but do study natural therapies. You need to use the pink grapefruit juice because of the pectin, which activates the liver. Also, the grapefruit helps the taste of the oil, so I reccommend it. Regarding the time, I think that you should keep with the specificied time of taking the oil and grapefruit mixture at 22:00 hours as according to the 24-hour Chinese meridian clock, the liver and gallbladder are most active from 23:00 to 03:00 - so you need to take advantage of this if you want a good result. Good luck! I am on the kidney-liver cleanse at the moment and am surprized at how much stuff is in there! Whew!