Nute burn, k def, or something else?

I’m in need of help, again. I’ve been unable to pin down exactly what I have happening here with this round. Similar symptoms in new clones slow to get going and a couple plants in flower, which is making me think I burned them as the young ones shouldn’t be wanting too much in the way of nutes just yet Have the girl in flower in a mix of stepwell living soil and vpw 30 ammended with gaia green 444 and 284. Gave her mineralized phosphate at half strength just after transition as well. Clones in same without the amendments. Issue starts with a slight tip burn and some yellowing on the edges, progressing in until it dies. I did give clones a gentle feeding with a liquid seaweed (227) at less than half strength, suspecting k def, but hasn’t seemed to help.
Also wondering if the recent rain has changed my well water composition, which I need to get tested to find out what all is happening there. Wondering if the ca and mg is out of whack and locking other things out. Ph out the tap is reasonable at 6.4 usually- but I do usually aerate for at least a few hours which brings it up and sometimes needs adjustment (done with tnb naturals up and down).
Finally, I did just go through a challenging hot spell and couldn’t quite keep humidity up enough to maintain a reasonable vpd- so maybe continued fallout from that?
Too many possible factors! Any suggestions appreciated!
Last photo is for context that I do kinda know what I’m doing, sometimes.

Potassium deficiency

hotrodharley said:

Potassium deficiency

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I thought that too, but was second guessing because I didn’t think they’d need too much at this point. And the girl in flower should have plenty there with the 284 topdress and liquid feeding. Whatchu think about a foliar feed with soluble seaweed (0-0-17) at 1/2 strength or less at lights off?

TimewasterOG said:

I thought that too, but was second guessing because I didn’t think they’d need too much at this point. And the girl in flower should have plenty there with the 284 topdress and liquid feeding. Whatchu think about a foliar feed with soluble seaweed (0-0-17) at 1/2 strength or less at lights off?

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Worth a try!

Good points here. I'd say K. I. S. S. your garden. That's my moto. Keep It Simple Smartie!

TheAmazingDoctorZymes said:

Good points here. I'd say K. I. S. S. your garden. That's my moto. Keep It Simple Smartie!

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I tell myself this daily, just a little more harshly. Curious though, what points are you referring to?

hotrodharley said:

Worth a try!

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So I have tried at lights off and again before lights on. Will see what happens in the next couple days as I believe foliar usually has a pretty rapid effect. For now, the problem continues - starts with a bit of yellowing on edges, developing into brown, burned spots ; skips the yellow on tips it seems and goes right to a bit of burn ….is why I bounce between overfed and def. trying to get a handle on this before it progresses into the abuse I’ve subjected the key lime pie x dosido (philosopher seeds, and some of the most beautiful herb ive had the pleasure of burning….so I’m kinda heart broken and very confused with what I’ve done to her this round after at least 4 or 5 successful runs ) next to this Gorillagasm. She started with basically the same issue but more extreme…..tried flushing her a few days ago which seemed to make things worse pretty much right away so I’m curious to see what happens in the next couple weeks. I figure it would take at least that to show results. Shame I’m already well into flower and don’t have the extra time for fixing mistakes like this
it’s just all leaving me feeling confused