Deficiency? Only Upper Plant

[Greenies]

 

[Old Salt]

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The image is too dark to make out more than some brown edges. An image taken with more light would help us make suggestions.

When asking for help it's important to give as much information as possible. Here's the suggested format:
Strain: CKS Crown Royale
# of Plants: 4
Grow Type: Indoor
Grow Stage: Vegetative
Container Size: 11l / 3.8 US gal caged grow bags
Lights: King X6 Dimmable 1800W COB LED Grow Light (300W from wall max)
Nutrients: GH Flora Trio and Supplements at 30% label strength
Medium: 70% coco / 30% perlite
Water Source: RO (from well)
PPM: not measured
pH: 5.8 to transition ± 0.03
Solution Temperature: 25°C / 77°F
Grow Room: Tent 2'x 4'x 7'
Temperature: 25°C / 77°F
RH: 40%
Pests: None