BNC auto, one of my girls is growing slow.

looks a little pale on top. Try moving the light back 2-3". if new growth stops getting chlorosis, use that as new distance at least at this early stage. (or dim a bit, whichever is more convenient). May need to power back up after that, but use the resulting length of stem between new nodes to dictate light power -- not too tight, not too stretchy. expeact great variation from seed to seed -- possibly a bit less within a "strain" , but then being an autoflower adds increase variance compared to photoperiod strains. never tell yourself - "i'm doing the same things to each" because it's simply not true in more ways than you perceive. Even so, some plants are simlpy runts and others are not.