What’s causing this?

[Hookahhead]

Hey guys, my first time posting in this section. I’m at a friends farm, we’re in the tropics. He has 5 different genetics 2-3 weeks into flower right now, but this is the only girl showing these signs. All of them are in native soil, right next to each other. There are a lot of leaves showing this symptom, and all of them look the same. Brown spots in between the veins, and a bit strange but one side of the leaf tends to have more damage. I checked with a loupe, and but couldn’t find any identifiable pests.

 

[Maple_Flail]

looks like Mag or Zinc deficiency to me

 

[wassupmane]

no pest
probably nutrient or ph related
just 1 leaves or 2 or more
sometimes bottom leaves can have small scars but its not a problem

 

[Hookahhead]

Most of the damage appears to be near the top of the plant. On closer inspection the plant beside it is starting to show the same symptoms.

 

[wassupmane]

probably ph fluctuations
organic ? how do you feed them (mL, mS,ppm)

 

[wassupmane]

hum .. i think it could also be boron deficiency
that can be caused by too much of an element blocking it

 

[wassupmane]

"Most of the time a boron deficiency comes from the grower over-fertilizing their plants. Make sure to avoid this so that you don’t end up with a boron deficiency in the first place. "

"A boron deficiency also might be due to a lack of potassium and nitrogen, in which case you should water your plants regularly with these nutrients. If your grow room is quite dry, you can use a humidifier to help lessen the symptoms of boron deficiency."

https://www.ilovegrowingmarijuana.com/nutrient-deficiency-boron/