First thought it was calmag, then maybe root rot, but now I’m thinking phosphorus? Any help would be greatly appreciated. Checked the ph of the soil and all 3 at 6.5.
I say you were right on the cal-mag,that dark leaf is looking rather glossy, makes me think nitrogen toxicity. I grow DWC, so I can't say to much about soil. If I saw even a little shine coming from my girls they get a fresh tank with no nutes to flush them. A heavy distilled water flush would be my advice,
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