More nitrogen or more 'part B'

Hey there AcidFarmer, looks like you have phosphorous deficiency to me, that's because of how the plant's leafs are yellowing in that weakish way as well as the fact you're not adding any during flowering which is when the plant needs it. If it was potassium the leafs would have colourful splotches on them, nitrogen is actually the only thing you're adding with the canna coco A, you should be adding part b which has PK in it , or very lightly adding PK booster. Right now you're NPK ratios are off and you could muscle through with all the minerals but now you should shift a bit towards using less additives and more NPK, especially P . Your NPK ratio is like 4-0-1 , you should be more around 2-4-4 , does that make sense? Hope this helps ! 🚀