do you check your pHYep, I notice that too. I'm not sure what is causing that. The strain is mostly sativa so maybe thats part of it. Maybe its a watering/nutrient problem.
I would recommend you add the nutes then pH balance as your nutes are likely altering the pHYes, I make sure the pH is 6.2 - 7 and then add my nutrients. I gave an extra good amount of cal mag with the watering today.