Well you're asking a hydro person BUT I'll be happy to give my wonderful two cents. I ask about ph because to me it looks as though there is something lacking....not too much of anything. in hydro the ph tells all....there could be what your plants need in your nutes but they aren't getting it due to improper ph. If that is not the case I'd say they are deficient in something but i'm afraid I don't know enough about soil nutes to say whether what you are using is ok or not.

Try this link and see if it helps you pinpoint the problem.....hope it helps.

International Cannagraphic Magazine Forums - The Complete guide to Sick Plants,pH, and Pest troubles!