OD

It's probably a P-K deficiency!! Sometimes too much N can cause PK deficiency, so flush the soil, and then you can rewater with ferts, in the correct % for this stage

kinda tough to know without what is being fed in a more resolved way. if you know the ppms, you can compare apples to oranges as far as brands and fertilizer mixes etc... Knowing your pH is solid is important too. the yellowing from tip-in at bottom is a symptom of N-deficiency. did the colorless necrotic spots show up later, i assume? Several things can cause the burnt tips you see. Mottling happens to older leaves on healthy plants... so kinda depends on how some of this evolved over time. if there are multiple different types of symptoms, i'd wager it's a matter of lockout -- interference in availablility due to how many other things are floating around. ratio balance is as important as concentration (PPM) of any 1 molecule the plant needs (soil is a different animal, but similar concepts at play... can have higher EC in soil/living soil cause a lot of that won't fit in through roots until it is broken down further by mocrobes... soillless is fed with fully chelated/fixated nutes.. ready to be absorbed and used) If imbalance is the cause, it's much easier to fix in soilless than in soil. simply change recipes and if not crazy far off an irrigation or two with 10-15% runoff will drop substrate EC down to new mix levels. if in soil, make sure you let top 1" dry and then irrigate until you get some minimum runoff to ensure the whole thing is evenly saturated. there are hints of overwatering but cannot be certain. Slightly earlier with soilless options, but judge by weight of the pot for best consistency... it'll be a similar volume of water needed at a specific weight.

BTW, your PH is perfect for growing in soil and just at the top range for coco. Good luck.