Frustrating issue white widow nirvana

I'm just starting the 2nd week of flower and I have a strain specific issue with my table if white widow (nirvana). I've had this issue in previous runs, but for the life of me I can't figure it out. From what I can tell it doesn't fit anything specific. Most of the plants are paler than I'd like, and much of the new growth starts with yellowish tips. I'm fairly confident this is not burn. Some of the tips eventually fill in green. Could this just be nitrogen deficiency? 3 days ago I sprayed epsom, and it greened up a bit, but I don't think it's a mg issue. It's like the leaves are trying to turn green from the outside first, working in toward the middle of the leaf. I just thought someone might have some useful input. Thanks. Can't figure how to add pix from my phone. I'll add them shortly

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