garden thanks dude, but we are just gonna go with a 400w cause we dont have the extra 100$ for the 600w. but would it be better to buy a 400w hps grow light system and a 400w mh bulb conversion or a 400w mh grow light system and a 360w hps conversion bulb? i've look and noticed that the lumens are lower for the conversion bulbs as apposed to the bulbs that come with the grow light systems...