need help with lighting in my new grow room

hi every one im new to growing i have bought a grow tent 1.2m x 1.2m x 2m and want to grow 3plants in it should i get the 400w hps cool tube or a 600w cool tube lighting kit?? since it is a small room will 400w be enof for 3plants im after top yeild and im unsure that 600w will be to much heat in such a small room thanks

The 600 isn't a whole lot hotter than the 400, so it should be fine. Also, I'd go with the 600 if i were you, because that size grow area will be really pushing the limits of a 400. Plus, since you're using an enclosed hood, I'd definitely go with the 600, because the 400 will be even weaker due to the glass in front of the bulb.(it's cuts down output) Someday when you plan on throwing a couple more plants in there, you'll be happy you went with the bigger light because you'll be able to pack it full, and still get good light output at the farthest edges of the tent.(where the 400 would fail)

600w, jawbrodts explination was a good one, so i'll just leave it at that.

yea!! what they said!!

thanks mate ill be putting pics up when im growing to show how im going

go with a 1000w and get two fans on your hood and a nice fan!