Hi
@ValhallasGarden! To me it looks like a combination of nutrient-burn + heat-stress. Your feeding schedule looks very strong, I hope you give them a break with plain pH'd water sometimes, or your rootmass must be very hot. And your pH is not acidic enough for soilless medium, try to stick within the 5.5~5.8 pH range or your plant's roots won't be able to handle nutrient uptakes. Plus I don't see any fans in your grow room but maybe you already have some, I've seen my plants doing this when the airflow was not good enough, adding a small continuous breeze helped a lot. To summup: 1/ double check your pH and stick to the soilless range, 2/ raise your light a bit and add a continuous breeze with a small fan, 3/ flush with plain pH'd water buffered at 5.5 and see how it goes after a few days. Hope this will help, let us know how this goes, and happy growing! 👊