Quote Originally Posted by Farmer Rich
2 x 600w HPS will generate much more heat than the CFLs you're currently using. In my flower room, I run 3 x 600w + 2 x 4' T-5 panels (8 tubes each); to cool it I use a 15K BTU window ac unit that comes on about a 1/2 hour after the lights come on and shuts off about a 1/2 hour after they go back off. This keeps the temps in the 70s with lights. Prior to this I used 2 x 1000w HPS with sun soaker reflectors; this setup produced much more heat than the 3 600s. If you go with the 600s, I also recommend that you get selectable digital ballasts; I personally like the Lumatek that allows the choice of 360, 400, 600 and Superlumen settings. Never use Superlumen, but the others are really useful if you need to turn things down because of the heat, which I do occasionally in the summer. If you go this way, make sure to just use 600w bulbs..

Peace,

Farmer Rich

Thanks for the input. What size is your grow space? I have my lighting that I'm going to use all figured out. I realyy need to know how to keep this space below 80deg without an a/c unit because I lack the window? I have fresh air that is consistantly at 62deg available at all times to circulate.