Hey guys, I'm growing one plant of Early Miss, it's auto-flowering so I've got lights and a fan going 24/7, it's been doing great so far but I'm noticing yellowing on the tips of the lower leaves and a bit of yellow colouring in the stem.. it's growing in ProMix formula purchased from Walmart, just feeding it water. A ny suggestions for nutrient deficiency or other causes? Any help is great. thanks in advance!!