Hi Spanishfly,
I'm on Day 4 too, and it's my first real Master-Cleanse (did an Ultimate Cleanse a year ago, it was different), so I'm no expert, but what I've read from different posts on Master-Cleanse Forum looks like you are getting some real junk out of your kidneys. Do you drink any water besides your lemonade? Why don't you help yourself a bit?
Since drinking water is considered some kind of kidney cleanse and is welcome during MC.
Oh, and do you see any kind of sand or anything unusual during your urinating and b.pee? Somebody described to have something looked like sand, can't remember where I've read it.
Off to drink my SWF.