Your strain says Gorilla Cookies "Auto" Good god man 2 auto flowers under a 1000 HPS? what a waste of time! If they were photo periods i would suggest 5 or 7 gallon pots, but you are growing auto's man, and only 2 of them. Auto's dont grow very big and don't produce large robust root zones, so if you grow an auto in anything bigger than a 3 gallon pot you're just fucking yourself over by wasting Coco medium and nutrients on a root zone that won't fill the pots. And you will be burning all that electricity and spreading all that light on empty space.
If you yield a quarter pound off those 2 auto's I'll be impressed. But more likely you'll get a oz. off each, which will be 56g from 1000w of light which is about as piss poor of production numbers as you could get. Only outcome that would be worse is 0g and plant death. Better do some re-thinking if I were you.
Jesus you people, stop buying auto flower seeds!!!