@Floran, I do think a ph and ec pen will be if great benefit and will help us to diagnose the issue.
It does look a bit like underfeeding but your in a light mix which would have enough feed for the first 14 day's so I doubt it is a overfeeding rather the plant is craving feed now as the nutrient in the medium had been used up. It does also look ph related so I'll keep checking in to see how you are doing ๐
With love from Humboldt county โ๏ธ
Kind regards
Team-HSO..
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