4 Crystal Candy XL AUTO - First Grow

18/6 or 20/4 there is no need to do 12/12 and will only hurt your yield. Hole this helps good luck

It does look like light stress. If you don't have an option to dim your lights and can't move your lights any higher, I would try to lst. In the past I have combined mild supercropping and lst on the highest points when I couldn't move my light higher. I would also add an extra .5 mL of cal-mag per gallon of feed water. Sometimes 1 mL per gallon extra. Adding CO2 can allow your plants to function properly with higher light intensity. You can also cut down the length of time that your lights are on. Because the light is closer, it's intensity is higher so you can run it for a shorter time with similar results. Research daily lighting integral(dli). It can describe what I mean about the higher intensity for a shorter period evening out for plant health. Those are the only things I can think to help with the light issue. Happy growing and good luck Bud!

Aside from raising lights you can reduce the time the light is on. You can try low stress training as well. You can reduce your amount of nutrients some, in case some of the color difference is partially due to over fertilization. I would increase cal-mag still as I said before. It can affect the plants ability to produce enough chlorophyll if they don't have enough cal-mag with high intensity lighting. Adding CO2 can help the plant function at a higher light intensity with extra cal-mag than usual as well. That's what I found in my research and experience. Good luck on your first grow Bud!