Also running a 1000w in a 4 x 4 with plenty of cooling. But the last run which was my first with this setup was light burned at 16 to 18 inches so now I'm keeping a better eye on light height. I honestly thought from research online people seemed to be running 1k at 16in. I guess its also strain dependant my red widow burned but my 1 blueberry cross held up great. Hoping this next run goes better. What Are you all keeping your 1k watters at.