You wana go with about 100cm at least so say at least 3.5ft, the more room the better mate.i got a 6400k blue spectrum and a 2700k red spectrum lights on the way in the post. headin out tomorrow to get a small mains fan and a lamp (dont have a spare one). got my grow box done up there (glass viv cover in tinfoil reflective side in) so just waiting for the seeds to germinate. would a 1 square foot by 2 foot tall be ok for the grow box?