Did you take enough clones to account for ones that might not make it? A buddy of mine always took twice as many clones as neeed, a little paranoid. Then he wouldn't loose hardly any and he would fuck himself over by trying to grow more than he could handle.

Are you keeping the lights on 24/0? The reason I ask is because that is what I have always done. But recently I read a post on here about the roots needing the dark time to grow, thus making the clones stronger with a greater success ratio. Just curious on your technique. Good Luck!