Northern Lights first grow

Hi @Berserkjibis! Avoid any kind of pruning after the 2nd week of flowering, each pruning session requires the plant to focus its energy into recovering, and might even lead to new veg growth. Defoliate instead! 👊

The first suspect when you have weird leaf symptons is pH, specially if you are using tap water. That been said, you have several burnt tips on quite a few leaves. You mentioned you top dresed the soil, perhaps whatever you used was too strong, because it does look like a slight nute burn. Before doing anything I would meassure your water pH, if it's too high, that's the more likely culprit, if not then flush the soil with pH'ed water.