What nutes are you using and how much? Tip burn could be too much fertilizer. I alternate every other watering. Also I add a half teaspoon of Cal/Mag to the water.
I'm using 3 teaspoons of fox farms blog bloom ... i might have had the lights too close idk if that would do this .. my other plants are starting to get frosty but this one has not yet .. this is one of my other plants
The Fox Farm Big Bloom isn't very concentrated, NPK ( 0.01 - 0.3 - 0.7 ). Maybe a pinch more nitrogen for the plant with yellow leaves. How often do you water? Let the soil dry before watering again.
I believe this may be nute lock caused by over fertilizing .. I'm gonna flush it tomorrow with a fe gallons of fresh water.. then hold off on notes till she recovers a bit