I'm about to renavate my current grow room. What I'm using now (the same ones I used for my first time) are these big dry wall screws that screw into the ceiling and have a hook on the opposite end (the part that's not screwed into your dry wall ceiling). Then you take the chain link from the flor or HID ballast and hang it on the hook from those. Anyways, are there better ways? That's all I could find at Home Depot.
When you screw into the ceiling, is that the ceiling of a grow box or the ceiling of a room or closet finished in drywall? If drywall, are you screwing into a stud? I would be concerned that a drywall screw into drywall only in a ceiling could pull out and your light would fall. A HID light falling would shatter and could start a fire. If you are screwing into a stud you are fine, if into drywall only I would recommend an anchor or molly bolt.