That does make sense, being nutrient burn.
only after 3 weeks you started feeding, even
at half strentgh. It most likely was too much
food for them. I would go with the hydro-guys
idea and flush. The next couple sets of leaves
will show if that improves the matter or not.
now to puff on some homegrown G-13xHashplantxNorthern Lights #5, peace