Try Ebay !!! My mate bought a 400w HPS + ballast for only $30 NZ........$15 US!!! Damn, that's cheap.

You will need a ballast without a doubt. Reflectors are always good if you don't want to waste precious light
s12fever Reviewed by s12fever on . Lighting info ??? Curious... Instead of paying alot of money for an entire bulb, reflector, and ballast setup online... I've seen bulbs at home depot for 30 bucks but what ALL do i need to complete the set up for an HPS 400 watt light? Mogul base, ballast? Where is the best place i can find this stuff? Online anywhere? Rating: 5