Some if my fan eaves are curling up. Y
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I’m going to guess here.
From the color of the main stock, when they where young, you up potted to soon, and watered to much n had a major Ca/Mg problem, and possibly have bugs in the soil.
Had them doing better then hit them with a heavy feed and now they are locked out .
I don’t think the curl is from light intensity because the lower leaves are curling 1st
I can see a plant in the back ground the did a more normal burn (yellowing tips) this one salted up n locked out. Letting them dry out to much is bad too.
I would calibrate your ph pen & ppm pen
If you don’t have one , get them n the cal fluid,
Then mix ph 6.5 RO water & flush
Once you see run off , check ph & ppm
If it’s running out at 5 , bring up the ph of the flush water to 7-7.5 , you want to bring down the ph run of to 6-6.5 and a low ppm
Check for very small bugs in the run off.
The last bit of water I run through the flush has a light dose of veg a&b n ca/mg n a root stimulus (25%ish dose)
I do this because you just stripped the medium and they need something while they dry out.