You say they just went through a transplant, but they look too big for those pots. Maybe it is just the angle of the picture. If they are not autos, I'd try topping them and getting rid of some of those older fan leaves that have seen better days. Let the plant develop some new, healthier growth. If they were in the dark for three days, it may have triggered flowering even if no signs of buds. Going back to veg will set back its development somewhat. Definitely needs some TLC. I'd test the pH before worring about adding any nutrients. When you did the transplant, did it look like there were any root problems. If so, its possible it just won't recover.