150 watt HPS ballast

i have one plant currently growing under 2 120 watt cfl's, which i plan to keep or add more lights throughout veg cycle. I also have one 150 watt HPS light but on the box it says it needs a ballast. i bought a mini ballast that can be screwed into a normal light socket and supports up to 150 watts but doesn't seem to work. where can i buy a ballast that will work and that i can find at local hardware store (i.e. lowes).

High Tech Garden Supply

GO TO EBAY AND YOU"LL FIND THEM FOR AROUND 30.00$ Just for the ballast

e-conolights .com I bought 2 150watt ballasts including bulbs $55 shipped.

high tech garden supply... Simply the best there is out there at unbeatable prices..check them out you wont be diaapointed

I bought a 150 watt HPS flood light yesterday and all i had to do was put a pig tail on it. and it only cost $ 53.00