How big should the room be....

I have a 400 watt hps how big should the grow room be for this light?:rasta:

The room may be any size, but you should block off a section that is about 3x3 of floor space and at least 5 feet high to use that size light correctly. Hang Panda Film to create your space most easily, or build a box.

400 watt hps is perfect for a closet, with minumun cooling: especially in the fall, winter and spring.