Ok so couple things you can likely improve but first how much of each nutrient are you feeding them?
I would not ph adjust my nutrients for a soil grow as these soils are prebuffered and will adjust the ph for you. Explained in the link
I think it's possible you are slightly over watering I'll link a thread on media and one on ph at the end. You should be letting the pots dry until they are light (like very light)... if you already are good stuff.
Would be nice to see a PH of the runoff to see where it's at.
Make sure the pots are up off the floor to ensure your root temps aren't affect by a cold floor.
Discuss different watering methods for growing your own weed from seeds. Our community members give helpful tips on how pot size and material, as well as environmental factors affect growing cannabis.
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In this article, we discuss proper pH levels for your weed plants; alkalinity, soil pH, tap water, and the effects of nutrients on pH when growing marijuana
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