Maybe its an defency of k?

not enough info or weeks to see the progression in diary.. your defoliation probably exacerbated it. you only have small leaves all over... this is not ideal.

Looks more like nutrient burn, could also be from not enough runoff. I'd start to monitor your EC of whats going into the pot for feeding solutions and go from their, follow their ratio guidlines on the feeding chat "listed below" but dilute to the desired EC. If possible maybe monitoring the runoff coming out of said pot if you get any. This helps you determining if the strength your giving to to strong or week, But that is also indicative on the leaves and how the plant is looking. When growing in soil its best to feed once a week and then water the remainder if it needs more. Soil holds onto a lot of the minerals and can get overloaded over time if your feeding like it is soil less with no runoff. I also don't get runoff with soil as I grow with amendments and use a more compact medium but if you add in enough perlite you can easily get runoff, and I think some runoff with liquid nutrition is essential. Biobizz also recommends adding in a enzyme product like their acti-vera. Your ratios are a bit different from theirs. and their ideal PH is aorund 6.2-6.3 but they say anything between 6.2-6.5 is fine, so your PH is a bit high for their lineup on paper but I don't think that your problem. most things are available from 5.8-7.2 range. https://www.biobizz.com/wp-content/uploads/2020/03/Nutrient-Schedule-EN-2020.pdf Good Luck!

Honestly since your leaves are curling up at the ends and it’s happening all over I’m thinking it’s a phosphorus deficient. Potassium the leaves curl down and the death happens up the edges of the leaf and not the tips. Hope this helps.