Have we flushed this medium repeatedly?? You have have a bit of nutrient lock-out if the Nitro doesn`t make a change in a day or two. If it were pure deficiency you`d see fast signs of uptake if your stem and growth system had enough and proper growth. I`d be thoroughly flushing and resume feeding, FULL vegetative feeding. I`ll stay put
KC
![Weed :weed: :weed:](/styles/smilies/weed2.gif)