600W is 50% more wattage and gives you a lot more lumens. If you're trying to do the whole room, why not shell out for a 1000W? if you've got any thought you might upgrade, might as well just get the big light and save yourself some money in the long run.
scagster Reviewed by scagster on . 400w HPS 6x5x8 grow room. Any Advice? Hey so basically im running a 400w Hps and have already built a enclosable environment that is 6 feet long x 5 feet wide x 8 feet tall. I was thinking of running a little more than half the space(5x4) for flowering because ive heard the 400 w is just not enough to power a 5x6x8 room full of plants. Also i think it would be ideal to have a 2x5 running with FL for my mother plants. Im goin to run 5 gallon grow bags with Fox Farms Ocean mix. Im using Bio-Grow, Tiger-Bloom, Root Excelurator and Rating: 5