I did experience something similar on my outdoor grow and it turned out to be wind burned. After looking through I did see that you sprayed your plants when lights are on and the water droplet may off rolled off the leaf and the streaks causing by the light itself, another could possibly be a PH as you did state it drifts from 5.8/6.2 which may off locked out a specific nutrient to causing the roots to lock or bound. And if your leafs are twisted and forming around a 90 degree angle then you're looking at broad mites, it doesn't seem like a calmag problem as calcium effects lower leafs to twisted whilst forming rust spots and magnesium causes the center leaves to yellow. One other I can think off may be a boron deficiency
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