Please help, what's wrong?? What deficiency

[Quick Draw Mcgraw]

Hi guys first post for over a year whilst I honed my skills, all except one?.
Every time I grow white widow I have issues!! Right I'm growing in plant magic soil with ionic nutrients,
This started in week 4 veg now had 4 weeks in flower and it's getting worse! Please refer to pics!,
Question 1 do I need to adjust my ph levels I'm feeding!? It's 6.5 with an e.c of 1.5-1.7?
I tested my runoff and ph is 5.2-5.6??? And e.c is up to 2.0-2.2?? Do I need to up my ph nute solution going in to make run off higher?
The leaves started at bottom with yellowing, I went away for a week came back they hah turn up at end gone to brown and crispy and just to touch they would fall off, even at the very top bud leaves, my bud formation has been compromised thoroughly, yield will be down 75% t least, I given up with them just seeing what happens, and for info so it doesn't happen again!!
It is def not nute burn, I was thing cal mag but supplemented with this to no avail
Please help??
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[joker_the_smoker]

post it in the infirmary section bro

[Quick Draw Mcgraw]

Cheers bud, il see what I can do!!��

[Bobthegrow]

It looks like a mag/cal deficiency to me, the red stem is the main indicator. I have had it and I couldn't 'repair' it, but you can stop it from getting worse by adding mag/cal. Just remember to add it next time you grow.

[Madmungo]

Cal mag mate, are you in coco?

[Madmungo]

Sorry mate just seen you're in soil, your plants are lacking cal mag but probably hungry in general. Sometimes less isn't more.

[M_C]

This is a duplicate thread that is also in the Infirmary so i shall close this one