does this curling tip look strain specific/toxicity/ deficiency

So my two girls are pure afghan under a 600 (just switched to hps)
i havent fed them any veg nutes in a while just camg then most recently ph'd water (tap unfiltered)
they are quite green ( so not believing deficiency), the bushier one has a couple(2-3) leaves at the bottom that are feeling more crisp but the rest is pretty soft ( kinda too soft) and obviously the leaf tip curling (one fan leaf was canoeing)

It looks to be all around the plant but maybe more towards the middle/top
Should i be concerned? i normally wouldn't care but because the leafs are so soft that was kinda throwing me off
though now that i'm thinking about it, i wasn't running the exhaust fan in the dark until this day so it was getting super humid in there and then would get pretty dry(swing of about 60-65% - 25-40%

looks like overwatering.

also how do they look in general?
the left one has survived some craziness and seems to be loving life, it has 4 tops now, and two more hopefully will reach up there
the right was only topped once (didn't mean to but just went for it after i broke it off) and has 4 and about 3 more very close to the top

could be, its coco and ive been judging their weights before watering so i don't know if it could be overwatering

they look decent. You really need to take pictures without the light on its hard for anybody to really see whats going on. Post better pictures and people can tell you more.