I will tell you one other thing i do.. When i lst like you have done, if there is any huge fan leaves covering new tops/growth, i pinch it.
When small i try to tuck it, so as to not take away from the plants growth. 6 weeks and after, i will pinch them off, as ive seen it not only help the top, but also the top that i pinched the fan leaf from... They are getting ready to hit stretch in the next 7 to 10 days. I would feed 500 + ppm up till day 40 and start fnb 700 to 800 ppm or 8ml per gallon. That is what i did. I used gh 3 part (HEAD RECIPE) for veg up until switch to fnb at 5ml per gal for a 10 days then 8ml per gal the rest of the way. Day 70 start topping off with plain ro.... for the remainder(prob 3 days) but your girls look good,, you are doing a great job. I am glad to share the nubie stage with you :)