hey there, what you're seeing is nitrogen lock out. Too much N led the plant to lock out , that's why you see yellowing starting from the base of the leafs going outwards starting with the oldest leafs first (because the plant isnt getting any N, because there's too much N, it's cannabalising the N from its own leafs) . You need to flush by watering with plain water until run off then adding like 20-30% more water than what you used extra. Remember in soil you should be feeding plain water twice then nutrients once. Meaning water water feed water water feed... you're only feeding once every ten days or so. Here the nutrients built up that's why this happened. Hope this helps ! 🚀