Right now I got a 540 watts and 2 x 590watts + a 90watts. I dont always run them full intensity. so out of 1800watts I ll often run between 1200watts and 1800watts. I got many switch on every light. Right now is crucial time because most of them were recently ''vegging'' and now just starting to bud, it's really important to give em plenty of light for the early stage when doing 12/12 from seed. Once the buds are halfway there I start decreasing the light. I just got the lights in October and I am experimenting with them. During the summer months I plan on growing with each light at half the power running only 900watts in the room and see what I get.