panta,
Let me first start by saying I am NO PRO. Also I have NEVER cloned mj (have cloned other plants). With that said let me say that I have seen peoples clones, and I have read ALOT on the subject. I have never really heard of someone just leaving cuttings in water.. Did you use cloning gel?
Most of the time when people clone their clones do turn a little light, and wilt. They say that this is the plant stressed out and it usually passes as the roots better develop. Also they recommend cutting much of the leaves off, and even cutting the leaves your keeping in half. When plants develop roots they focus their energy on producing roots, if they have too many leaves to take care of at the same time then their energy is dispersed to too many places. As a result they stress out. Generally they bounce back in a couple days.
This is all that I know, and I hope it helped. Hopefully some experianced people can give you some more reliable and skilled advice. Good luck.