Man, cool! I also grow Afghan Auto from BLK Seedbank. Your plants look healthy, but grow too slow. There might be too reasons. First is because of absence of a night time roots develop very slow. Second, the cant contribute all needed nutritional elements. So try to up ppm to the level 250-300. And check carefully pH of water used. 5,5 is the lowest border. Are u shure that it is not less?
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