Over the last 2 weeks our shower has started to smell. My "google-foo" says it's Hydrogen Sulfide gas, and since it's only smellable in the hot water, not cold, that it's probably being created and not vented in the hot water heater.

Water system is a well and hot water heater is new. We are renting the house, so my hands are somewhat tied on a path forward. Google says possibly replacing a heating rod in the water heater.

Any experience with this? Costs, solutions etc. ?