One of my babies starting to look really bad HELP

I ADDED 2 NEW PLANTS TO MY TENT IN THE MIDDLE OF ANOTHER GROW NOW ONE OF THE BABIES LOOK PRETTY BAD THER GROWING IN COCO UNDER 3 LED LIGHTS UNTILL MY HPS ARRIVES NEXT WEEK

Did you wash your coco, before you potted???????????????????????????????????
How much have you fed????????????????
What's your ph??????