Looks as though that's a 400w metal halide. How well it performs will be determined by the size of your growspace. It should suffice in an area under 9 square feet. That being said, it's not ideal. MH lights produce more blue light, thus making them perfect for vegetative growth yet a bit lackluster for flowering. Don't get me wrong - it'll work and you'll be happy with the results I'm sure, but it isn't ideal
Candles work best. lol, no but it should work if your just looking for something to do. If you want to get serious grab a 600w and neck it down if needed. (HPS/MH) Dual