Don't throw in the towel just yet. My ketostix never went above trace my first week, however I lost 8 lbs (and a total of 3 inches since then). I was drinking over 100 oz of water. Dark purple is usually an idication of not drinking enough water.

If you're feeling fatigued and weak it may be a sign you're not getting your vitamines and minerals? are you taking supplements? There have been numerous discussions on the topic, here's one that may help http://forum.lowcarber.org/showthre...&threadid=16014

Good luck!

Nat