All standard hot water heaters have an magnesium anode rod that can be the sole cause of a rotten egg odor that comes only from the hot water. The magnesium anode rod in water heaters is meant to corrode instead of the water heater itself.
When feeding your hot water heater with soft water, this magnesium rod can experience a chemical reaction that produces hydrogen sulfide gas. This gas has a rotten egg odor.
By simply removing this anode rod and thoroughly flushing your hot water tank, you will eliminate your rotten egg odor.
By removing this rod, your hot water heater’s life may be reduced slightly, but that is a small price to pay for odor-free water.
If your rotten egg odor is in both the cold and hot water, then iron bacteria has most likely invaded your water softener. Crystal Clean will solve this iron bacteria problem.