mh ballast matching wattage of bulb...just buy a kit for that bulb...ebay around $50
you don't need the reflector.(a common misconception is that you need to buy this big reflector,DON'T) If you build your grow area the ceiling will be a reflective white or mylar and without reflector light bounces all over...really lights up the place...also, 10-12f degrees cooler...