Dude that is nute burn, classic example. I have that happen each time I bumped up the nutes a few mls then the plants would adjust and be happy with the increase until I increased again. I tend to start at 5ml of veg or bloom nutes and increase it 3 mls each watering until I need to start decreasing the nutes at the end of flower. Try feeding a little less.
Ok just saw you are in FFOF and using Botanicare. That is excatly what I am using. It is nute burn I am sure of it. I found that I could not feed any grow nutes in veg without getting burn, not even 1 ml per gallon. I went threw 5 weeks of veg with no nutes only CalMg, Bio Root and sweets and my plants stayed lush and green. FFOF is pretty hot and has enough nutes in it for at least most of veg IME.