Water heater smells like rotten eggs or worse? In areas with sulfides in the water, like many well systems in Palm Beach County. (Jupiter Farms, The Acreage, Palm Beach Country Estates, and Loxahatchee), there is a reaction with magnesium anodes which creates hydrogen sulfide gas. The gas smells like rotten eggs or worse. 
A powered anode rod can solve this issue. Electricity is used along with a titanium clad electrode to protect the steel in your water heater. No chemicals are added to the water and this will stop the smelly water created by the chemical reaction. This powered anode rod will also extend the life of your water heater tank.