Low humidity factor? Im at 75 f and 50 humidity during lights. Low 40s humidity when off. Top of plants doesnt have these leafs

@Bernie Five Ok so the plant looks pretty good overall. The curling leaves makes me think its getting nitrogen toxicity but your EC is fine. Maybe this particular pheno is a bit fussy when it comes to feeding as doesn't need a much as others.

week 5.5 flower 11x10 room

flood and drain rock wool 6x6 cubes. water 2x but sometimes one heavy watering works.

running heavy athena pro

2.7 ec 5.7 ph

run off only goes slightly higher to 2.8-3.0 ec with ph 5.7-5.8