You should provide a bit more information if you are looking for advice. If you want answers let people know the following... How long have you been in posession of the clones?, Were they healthy when you aquired them?, Did you transplant or are they in media they came in?, Have you applied any fertilizer?, What light source and power are they under? My first thought is that they may be shocked due to someone feeding them too soon, before the new roots have a chance to mature and harden up to the point they can be subjected to fertilizer. But, until you provide more detailed information it is all conjecture.