Ron- I did some searching on many hydroponic forums. Seems that LEDs are the lighting de jour. I am reserving final judgment on LED-distance-to-plant until when I conduct my own experiments. The hydroponic setups I've seen that are being used to grow "regular" plants seems not much different than setups that use conventional lights. Apparently LEDs are big with the marijuana growers as they don't suck wattage or produce a large thermal signature...just FYI...there is a lot of good information to be gleaned from those law breakers.