How many hours a day are u keeping the lights on? And its hard to tell cuz theres no pix for me to look at them. But they start off slow, wait till they are 21 days old, they should pop their pistols and show there sex at 21 days old. I wouldnt stress over it, they start out small but they pick up an grow fast. Keep an eye open around 21 days for the pistols. And keep me updated. Im about to harvest 1 of my pka within a week or 2