Brown spots on leaves deficiency?

I’ve increased calmag & potassium and seems like its getting worse today.

Up the calmag and see what happens.

I declared this plant dead weeks ago but it kept wanting to grow regardless so i let it. It got fine for a week plus then this again. Everything is in check ph/ppm etc. ph runoff is 6.2. Yes it is in coco and you could be right about a bad mix. This is an unusual problem that i never face with what im doing and giving with past grows. Currently ppm in is around 700ppm and runoffs around 500. Not sure what else to do, cant get new coco anytime soon yet.

could be potassium deficiency. i'd lean that way over Ca deficiency due to burnt tips ensure pH is not the cause... check what you are feeding and adjust. you have a lot more info at your fingertips... use it to eliminate possibilities. i don't see a diary attached to this plant, but based on your do si do auto diary i am assuming you use coco / soilless. This could be a bad batch of coco. while it reaches equilibrium, it'll release K while it bonds with Ca++, possibly Mg et al, any positive ion in high enough concentration to replace K. Anyway, this will be a temporary phase. Basically, you are buffering the coco as you grow, which is not optimal, obviously. So, i'd becareful with any major adjustment to nutrient mix... if you can calculate your ppms of each element, can compare to a table in any recent diary of mine. Ca/Mg/S will vary due to differing tap water. mine is hard, so you may need more than more of any 1 of these. looks like it could up-pot safely. knock off loose, use different batch of substrate. when i used a shit brick of coco, it took about 30 days of normal irrigation before it got out of its funk. heck, i even soaked it in cal-nitrate for one of the runs.. still had sickly plants for first 30 days.