I don’t know. I think I’m going to back away from my advice to buy a powered anode for a little bit. If you can pour peroxide into the heater and the odor leaves the hot water, then that would indicate an odor problem in the water heater that the powered anode would solve. If it still smells, then the powered anode wouldn’t fix it. It may just be that you have enough sulfur in your water that it’s noticeable. That happens sometimes. I don’t know of a cure.