suggestions on mutually exclusive pins

[arjepsen]

Hey.
I'm trying to program a controller for a beer brewing machine.
The machine itself has two tanks, with two SSR's controling the heater elements.
The elements pull a bit too much current to be used at the same time, so I want to program them to be mutually exclusive - so only one pin can be used at a time.

The program will possibly use a pid algorithm for heating during the mash-stages, and change to a pwm signal during the boil stage.

I'm a happy noob at c++, so I might need a some advice on how to implement this idea.
Any help, or pointers to solutions?

Regards
Anders