Plant looks fine dude, don't tweak. I would water less and maybe lower ppm. Doesn't seem bad enough to warrant flushing the media.. but you could certainly do that (I wouldn't unless the burn is getting a LOT worse). She's barely starting to stress, so you shouldn't too hard.
Just read the part about this being since she was under the light... If you're doing a foliar feed remember to mist the underside of the leaves. Also using a wetting agent will prevent the water from beading up and creating tiny magnifying glasses all over your babies. GL!