I use 3 150 watters (magnetic ballasts)in one big reflector (modified roadsign) I can raise the seedlings with the one in the middle, then switch to the two side ones for veg, then put all 3 on during flower, works well, saves cash and grows big buds.
with all 3 on it only raises my temps 4 degrees over the room next to it.
4x5 Reviewed by 4x5 on . 150W Digital Ballast, worth it? So I'm hunting around on Ebay and I come across a 150 Watt HPS Digital Ballast. I know digital is the "way" to go as it's more efficient, cooler temps and the bulbs produce more lumens. Question is, for such a low power bulb, would it really make that much difference over your standard back yard mechanic ballast? eBay: Digital 150 Watt HPS Electronic Ballast Grow Light 150W (item 330091251497 end time Jun-21-07 10:11:30 PDT) Rating: 5