Auto jack herer problems..suggestions please

I'm growing some autos right now. The other two seem ok(ak 48 and Pineapple Express) but the jack herer has burnt leaf tips. I thought it might be over water so I'm letting them dry out. I am using ffof and thought the nutes in the soil might be to hard on it. I haven't feed any nutes at all. Just what's in ffof mix. I thought maybe it needs a small dose if nutes but its only 2 weeks old. Was gonna wait till about 6 weeks on nutes to add. I'm running 400 hps my temps are 78 and humidity is 48 to 50 lights on. Any suggestions? Thanks tbone

how far are your lights away from you plant? looks light light burn to me. im currently growing the same a jack herer with cfl lights and i have a little light burn.

also the leaves turning down like that may be over watering and light burn. do you water with the lights on or off?

The leaves canoeing and becoming a very dark color where they canoe.
Looks like a classic case of nitro burn

The lights are about 2 feet away and I water right before lights come on. I'm using ffof with perlite mixed in. I heard ffof was a hot soil. Might be to much for jack in the early stages. Have fed no nutes to date. So if its nitro burn then its form straight soil. I hoping she will grow out of it and adjust to soil.

You'll get that problem once in a while when using fox farms with small plants. Next time try mixing happy frog and ffof when they're small, then when transplanting to a bigger pot when the plant is a bit more mature, stick them in with all FFOF.
The plant still looks like she can be saved. Good luck with your grow

you can always try flushing the hell out of it. when i nute burned my plant earlier in the grow i flushed and cut off the sick parts.