You just want to use the foxfarm nutes at about 1/3 of the recommend strength. I talked to an old employee(of Foxfarms) who know runs a dispensary now.Who agreed that 1/3 was the best dose and that he uses it in that manner with his plants.
First off, You can move the CFL a bit closer to those bad boys. You also want to put a humidity dome over them and keep them moist. Now you could try taking the shells off, I've never seen anything like this before though. I believe the plant my find a way to shed it naturally but if not you...
I don't like rooting clones in Hydro and then putting them in soil. I find that the clones generally burn easier and they take a little while to switch over from the rich hydro climate (Slowing down the veg process). I now do all my clones directly into soil and have great success with it...
While I'm not completely sure what type of burn it is. It is burn, Try letting up on the nutes a little bit. The leaf is not ruined, You only want to trim it off if it gets about 50% yellow.
Hopefully that helps, Good Growing.