a lot of people recommend cal mag for led.
I have a theory that that is just treating the symptom.
With led the plants transpire a lot. I think this causes the plant to use more nutes than it really wants, leading to nute burn and some deficiencies. I'm putting that to the test this grow by backing off on the nutes.
If you are using this as a foliar feed, spray the underside of the leaf, that way you avoid burning.
@sanguine is that right? You use foliar a bit don't you?
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