I’m seeing brown on the lower leaves. They also ...

hey there, that's textbook calcium deficiency and magnesium deficiency , you can tell by the way those rust spots are , that's calcium, the way the leafs are yellowing on the edges that's the magnesium deficiency. Nothing simpler to fix, add cal mag and the problem will stop spreading immediately and the plant will completely recover in less than 10 days. However you have another problem which you did identify which is nitrogen excess causing lock out : that you can see from the "too green" aspect of the leafs, but the lock out symptoms are the burnt tips and the yellowing from the veins outwards even though you are actually adding N and it looks like lack of nitrogen . you should really find a more appropriate NPK ratio, in hydro the problem will stop spreading quite quickly once you dial that in. Hope tihs helps ! 🚀