Deficency? Burn?

Looking at your diary I do not see any EC/PPM values For the feed your giving. This could be a lack of N or Mg it could also be a buildup causing some issues taking up other nutrients. Given that your growing in soil it might hold onto a lot of the nutrients you have been feeding it for weeks. I think a flush might be in need if you have not been getting any runoff in the previous fertigations. If you get runoff test its PH and EC, might be a sign of what happening. Lower EC and high PH means it needs more if whats going in is ideal. higher EC and lower PH means its getting to much vs whats going in. not using all the feed up and its building up. Also the recommended feed chat is 4ml/l, no idea if this will be good or to much I don't use Advanced Nutrients. I think their brand its diluted overpriced and has bad practices. Good Luck!