Well Yer both kind of correct --But , Any way -- LED will not as I said in the post put out the Blue or Red that is needed. and Yes there is a ballast that is for fluorecent lamp lighting. LED is for energy and heat consuption as He said and without the graph. To test to see if it is a good light type is- If it puts out heat at the lamp--- GOOD TO GO ! Incadecant (light bulb) is low due to energy loss and uv at a distance. HID is high. HPS, MH, ect. OK Go to the Grow shop and see if they sell LED for hydro.p.. And if so ask how it worked? PS: I did not say blue in the post Sorry. deluxestogie, That is what I was looking for on input-Cudos- However LED is not in there.It is like putting the seeds in the car with the dome light on.It is a low voltage design to cut energy cost only Thank You guys, got to look at all the factors and teach as well. You are teachers. I am using 400w HID on My set. some use 4' ballast tubes.They sell grow lamps for them. Seen some nice ones at that here for2014 Good job folks.