Looks N deficient, What's you lighting schedule? I guess by the pics your still trying to vege them?

CoCo doesn't have any nutes,... so YOU have to feed the plants,... Looking at your feeding schedule (or lack there of), I'd wager that this is the source of the problems.

I've got no experience with CoCo,.. so that's just my "Gut" feeling,... hopefully one of the many experts will chime in soon!