Leaves getting worse! Day 27 of flowering

Hi guys

I posted pictures not long ago of my leaves showing what turned out to be a sign of calcium deficiency. I bought calmag and started foliar straying in the dark cycle and they're not showing signs of improvement. In fact, they're much worse. This is what the majority of the leaves look like...



Looking at that leaf alone, what is it likely to be? Tips burning and curling, getting lighter nearer to the edges...

Recent problems:

1. pH fluctuates quite a bit, this could be extreme nute deficiency, but...
2. I've noticed the nutrient solution increasing in ppm over time now, which must mean they're taking up less nutes. I checked just now and the ppm was way too high

Then again, the 2nd problem could be due to pH lockout... in any case I still want to continue using calmag on the foliage since the nutrient solution changes in composition very quickly I use NFT 424 systems.

All help appreciated. Thanks in advance

flush them then add the calmag to nute tank wiv ur N-P-K THIS should help

check this out. GL

https://www.rollitup.org/newbie-central/610029-magnesium-nitrogen-def.html

Thanks. The responses vary a lot in that thread, if anything I'm more uncertain about the conditions that are causing the problem.

I think my best option is to flush out the root mat and nutrient solution for a day then see what happens when I add nutes again, adjusting pH after. Think I'll continue to use the calmag spray.

magnesium or potassium deficiency....
are you using rockwool?