they sell cfl lamps in difference sizes and colors. Warm white is recommended for bloom cycle and daylight is for vegging cycle. (Cool White is 4100K and not a very desirable spectrum for plant growth). Cost can be a factor, 23W size can be found for a buck each, 48W can be found from $5-8 and larger, specific grow lamps and reflectors can be found and they cost quite a bit more. I would use 65-100 watts per square foot of CLFs.