If you get ambitious you can make your own food for a smaller price. From the grocery store:
Lobster Tail
Saltwater Shrimp
Scallops
Squid
Clams
small amount of fresh garlic
Add in:
Selcon
Spirulina (powder or flake)
PE-Calanus
Mix it in a blender (to the granularity to fit the size of fish you have), then store in very thin sheets in zip lock bags. The thinner the better, as you will find it easier to break off a piece when it is frozen. It doesn't take much of each of the ingredients to come up with a month's worth or more of food! The seafood counter grocer always used to look at me strange when I would ask for 2 to 3 shrimp, same number of scallops, etc, but I here in Florida it has become more common for reef owners to do the same.
Needless to say you can use any combination of the above or add additional ingredients (octopus, saltwater line fish, etc).