You need the bak and the start, I wouldn't start the system without those two. The food will be needed, but you can wait until later. You have to be careful with this system, constantly monitor your alkalinity and potassium, and work up to full strength over several weeks, but you can achieve excellent results. If you really want to play with fire, I can give you some ZeoSpur which lightens your corals overnight. Good luck and check out the forum that goes by the same name as the product if you haven't already. There are some very advanced people over there and not all necessarily using the product.
Dave