I've got the same problem on some plants that has been feeded with the same mix than others that are very healthy. I don't anderstand, i think it's related to a root problem but i don't know which. They all had a root booster ( GH bio roots ) some are fine some are ugly. I don't think they will recover. I did not give nutes before 2 weeks of veg, only diamond nectar and bio roots.
Fhydro