400w HPS grow question

I just bought a 400w hps to flower my plants and was wondering how big i should make my grow box. I was going to use my cfl's for the whole grow but thought better of it.It's my first grow so i want to do it right. Thanks.

you could do 3x3x6 grow box depends on how much space you have. One important thing is ventilation this is a must in any grow room, especially when using HPS.

400w hps covers something like a 3x3 area and the heat it puts off will let you get it to 18inches above the plant with good ventilation. I have my light 15 inches from my plants.

Dj1209 said:

400w hps covers something like a 3x3 area and the heat it puts off will let you get it to 18inches above the plant with good ventilation. I have my light 15 inches from my plants.

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I have my 600w in a cool hood in a 100x100x180cm tent I have it 10 inches from the top of my plants.

I've got a 400w HPS in my tent which is 1100mm wide, 650mm deep and 1200mm high and it seems to fill it with light quite nicely.

My tent is 4x4 but my canopy is 3x3. It gives me a little room on the sides for training and airflow.

I am also using a 400W HPS/MH switchable. These guys are pretty much on the money. I keep mine a foot or a little more from the canopy. I haven't had any issues with burn or things of the sort. No light damage is what I am trying to say. Just test it out at different heights and see how they respond best to the light. How many of the girls you got under it?

i got the 400W HPS/MH switchable too. it looks like cool little unit. how much heat should i expect? i'm gonna vent it out a window with a 4" line so i should have good air flow