metal halides emit more of a blue spectrum of light, the wave lenghts are shorter) HPS emit a more red spectrum( it all has to do with a metering system called Kevin) during the fall months, the sun is lower and emits a SLIGHTLY different spectrum than when in the summer time.. in my opinion, metal halides are the best way to go...K.
heavymetal Reviewed by heavymetal on . Flowering with a MH I know you can, but what are the differences between this and hps, i know there are some but i dont know the specifics. Im flowering with a Sunmaster MH bulb which says because of its red spectrum properties its good for flowering too. Rating: 5