help asap

I woke up this morning and looks like 1 of my healthy plants has problem now defiantly isn't a def because the soil is happy frog / ocean forest and they just got putt in bigger pots ...is this heat stress to hell and back there under 600w hid and 2 weeks old I never put them under the hid so early but could this be causing it there is air flow and a fan in there but could like just be to strong for babys

How close is the light? Looks like it maybe TO close, so yeah its heat and SLOW down that fan some. 600 is kinda strong this early, I start kids with T5's and move them to a 600 for veg and then move to a 1K for bloom.
How often you water? Water to soak soil and water every time you put your finger in to the first knuckle and it feels dry.

Start using a CalMag now! Your showing LOW mag. !

pH should be watched closely at this stage too. (Yeah I said it,,,,pH soil)

Just because it's HF/OF sure don't mean your not gunna get a def!

The third pic is def heat burned
Also be very careful here. I see many on RIU quick to identify deficiencies when the truth is its already nutrient overload.
They're young still and already in FFOF soil. I wouldnt add anything to it for awhile yet. As far as the heat burn goes I've had the same issue when I move my babies from the CFL nursery to under my 400 MH lights. It can be hard on them to adjust to such an increase so quick. By the looks of the 3rd pic I'd back that light off for a week or so and let these plants adjust.

^^^^^^^^^^^^Yep, you are smoking them wayyyyyyy too soon............

I started my seedlings under a 1k mh and had no issues. I kept it about 25-27 inches from the tops and that seemed to work well. I also started with ffhf but I am running that soil all the way through flower.

I took the hid down and putt my 4 tube t5 flurescent in its a lot les heat hopefully it will help them to recover then in week or 2 when flowering comes around ill pop them under the hid again