i got my info from Sanjay as well. Scuba_Steveo and I just went through this not too long ago......IMO the best choice of bulb for PAR, power consumption, and heat (or lack thereof) is the 250w DE running off an electronic ballast. The new coralvue ballast with the 3 year warranty cant be beat, I should have gotten those instead of these Hellolights which fail from time to time. Trying to get wrranty work on the Hellolights (ARO) is near impossible as well. And, the coralvue pendants have cooling fans. Heat has never been an issue in my tank, and I have 3 pendants in an enclosed hood.