Quote Originally Posted by ghostsurfer
A 250 watt fixture will supply enough light to cover a 2.5 foot by 2.5 foot grow area. (6 plants or less)
A 400 watt fixture will supply enough light to cover a 4 foot by 4 foot grow area. (12 plants or less)
A 600 watt fixture will supply enough light to cover a 5 foot by 5 foot grow area. (18 plants or less)
A 1000 watt fixture will supply enough light to cover a 7 foot by 7 foot grow area. (30 plants or less
I dunno, these seem a little outdated, its generally recomended nowadays that
250= 2 by 2 ft
400= 3 by 3 ft
600= 4 by 4ft
1000= 6 by 6ft
although I grew under a 250 watt light in a 2.5 by 2.5 area and got an okay yield with strong buds