If it says its a 150w HPS, then you only want to be using a 150w HPS bulb in it. There are 'retro HPS-to-MH' bulbs which are MH that run off HPS ballasts but they cost a bit more and a 150w one will be hard to find (they're usually 400w+). I'd say find a 150w HPS bulb and you're good. Does it...