Leaf problem

Hey hey ! You give way more nuts to your girls! At the stage she did not need pk13-14, and I think your light is too close! Try to flush your plant !

It looks like burn for toxic soil. I had the same issue earlier in my current grow. I flushed my plant with pH'd water and the problem stopped dead in it's tracks.

Light is way too close for that big of a light. I see deficiency, and toxicity. Are you getting proper drainage when you feed? I think your issue is a salt build up from not enough drainage. What is run off ph? Ec?

I agree with @Organoman, look at your leaves they are dark and glossy, to much feed. Use a EC pen to determine the ideal feeding concentration, use the ratios provided by the manufacture but then dilute it down to the desired EC. Look up EC if this is new to you. Most companies over feed so you buy more nutrients. and If you not watering with some runoff with hydro nutrients they are going to build up regardless. Good Luck!

Cal/Mag deficiency. Light is too close and too intense. I grow using MarsHydro FC6500. Set up the light at 100cm, using 25% in Veg and 50% in Bloom.

Yes, burning from over feeding/fertilizer salt build up in the substrate.