sorry double post
tomm01 Reviewed by tomm01 on . Answers about CFL, HPS, How Much Light... Although I'm still kind of a new poster, I keep seeing a lot of the same comments--many of which are answered an Dr. Khronik's excellent El Cheapo Guide to Lighting. But there are a few things I'd like to add in regard to watts, lumens, cfl, hps, and efficiency and how much light you need. Maybe this should be stickied? Watts have nothing to do with light or growth. Watts measure how much power a light fixture uses to produce light. You can tell how efficient a light bulb is by looking Rating: 5