@kovidkough has pretty much touched on the points to help improve grow.
Your plants are looking about as good as it gets ( especially to those wondering about FFOF soil ) , healthy green and growing fast.
Adding “ more “ Nutes to this will just wreck them. Let them begin to exhaust some of that medium on water alone , there is plenty of feed let in there.
FF Nutes run pretty hot ( disregard feeding schedule - too much for most grows ) and let soil do work. You will find simply adding
more FFOF to top soil is far easier and trouble free ( since plant is used to it ) . Look at LST for training them , especially since stems / branches will still be fairly pliable.
Yes , you can “ clean “ up the bottom areas of your plants to help air flow and light penetration ( which is a weak point with blurple ).