Hello, Yes your Girls are stretchy, a bit to much . Stretching means always they dont get enoughLight.or the Qualitiy of light is not enough. Normally i would say 600 w Hid would be enoughfor them to grow nice and dense . If i look at the pictures everything seems to be good.
BUt your plants show lack of light.check your parmeters ( really 600 w=?), maybe change the Bulbs .Happy growing
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