What hooks are you using?

Never had a problem with Gamakatsu SC15s rusting. All mine sit in those cheap Plano compartment boxes. I do have Z rust "tablets" in each box, but those are over 4 years old now.

Maybe sitting in the garage is the cause of your problem. If it's in Florida, surface rust is a problem down here. Take a look at the rotors of cars that have been sitting for a period of time...