Seedling: 600w blurple light height in 2'x2'?

You will continue to get varied answers. I have used my 180W LED array for seedlings, but that was at 24" I think suggested clearances are for established plants, and don't include seedlings. I would mount that(600W) light as high as possible for "seedlings". Then drop back down, once you are in vegetative state. At that point, your strain comes into play, how low you go, but if you miscalculate, you'll wind up doing LST in flower, which is kind of a wild ride. Horizontal buds.......Yikes. If your 600W has dimmer capability, I would crank down that intensity.

I would say start with the manufacturer recommendations and start experimenting.all strains are different,some will like it if lower your led and other don’t ✌️