Hello all, I am currently growing under 5 100w equivalent bulbs, and one on the side for canopy penetration. You can easily get the 100w equivalent cfls at walmart, home depot, lowes, etc. However in my area I could not find the larger 42w 150w equivalents anywere until my ladie drug me into Target what did they have??? The 150w'ers for 6 bucks. Not a bad price. Just a little info.