How to protect/repair a pitting aluminum boiler

[popeye]

I'm really pleased with the temperature stability of my microcimbali, but its experiencing significant and continued pitting due to the aluminum boiler. I'm currently using water passed through a commercial ion-exchange softener. Any suggestions for either plating the boiler or stopping the pitting? Would some sort of cathodic protection using magnesium be any good? Any chemists - would that provide more magnesium in my diet or would that killl me?