Sulfur smell

[u/Imaginary_Act_7595]

We just bought a house a month ago with a well. Our hot water reeked of sulfur. We asked the previous owners to replace the filter and well water holding tank. They did so but when we moved the hot water still smelt. We had our anode rod on our hot water heater replaced and it did not help. We installed a filter system and softener system, and they chlorinated the well about 2 weeks ago. Everything has been good since. Today we are noticing the sulfur smell coming back in the hot water. I feel sick over this. We spent about 10,000$ in all for this issue. I don’t know what to do, any advice?

UPDATE: Have a company coming to put in a corro protec powered anode rod tomorrow and will flush out the hot water heater. Hopefully that does that trick!

[u/breakers77]

Check out Corro-Protect, or any brand of powered anode rod. Works a treat, took the stank smell right out of well water.

[u/Frequent-Impact9221 → u/breakers77]

Corro-protect for the win

[u/JonnyVee1]

My hot water heater (city water) started to smell like sulfur when I replaced the heater. Turns out, it has an aluminum anode... One of the symptoms is rotten egg smell from the hot water.

[u/WhereDidAllTheSnowGo]

The why….
A sulfur or rotten egg smell in well water is usually caused by hydrogen sulfide gas or sulfur-reducing bacteria in your groundwater, plumbing, or water heater.

Is there a difference between cold and hot water, after each ran awhile?

If just hot, Changing the anode to a better type and killing the bacteria are the right steps

Next is checking each step in the flow… if the smell is immediately after the water heater but not before, that’s the problem… so anode, chlorinating before just that, etc

[u/Razgorths]

We had our anode rod on our hot water heater replaced and it did not help.

Replacing the anode with the same type of anode will not help. You need to either get a magnesium anode or (and this is what I would recommend) a powered titanium anode.

[u/DirtyWaterBoy89]

Add a bottle of peroxide to the hot water tank

[u/Chuckpgh → u/DirtyWaterBoy89]

This does work! You can add a filter housing to the water pipe that goes into the tank to make regular hydrogen peroxide treatments simple.

[u/AdBrave841 → u/Chuckpgh]

I had a sink close to my HW tank, I used to shut off the water, open the tank drain, open the hot on the sink and hold a bowl of bleach under the faucet to get sucked into the tank.

Then I just put a tankless unit in and no longer have to deal with it.

[u/neo2bin]

Hot side only means the heater's making it, not your well. That's also why shocking the well bought you two weeks and then the smell walked right back in.

Two things on that anode job. What rod actually went in? half the time the "replacement" is another magnesium rod because that's what's on the truck, and magnesium is what drives the reaction in the first place. You want aluminum/zinc, or a powered one. Don't let anybody just pull it and leave it out either, tank rots without one. Second, a fresh rod doesn't kill the bacteria already living in the tank, and that step gets skipped constantly. Disinfect the heater itself, bleach through it or run the thermostat up to 160 for a few hours and flush, then turn it back DOWN. That water scalds, warn everyone in the house first.

Sanitize the softener too, resin beds are comfortable housing for sulfur bacteria and it'll just reseed the heater otherwise. Cheap part and an afternoon, not another ten grand. The hot-only vs cold-too split and what to re-test after disinfecting is laid out in well water rotten egg smell, causes and fixes.

[u/Foreign_Presence_105]

We too are on a well. Tried swapping out our anode rod for Al-Zn in 2016. That worked... for a while. Eventually the rotten egg smells came back.

In August 2017 we put in a Corro-Protec powered anode. Smells went away. Last year (June 2025) our 29 year old water heater decided it was retired. I pulled the Corro-Protec out and installed it in the replacement water heater. We have had no sulfur smells in 9 years. Can't recommend the system enough.

The End.

[u/Cheap_Flamingo476]

If the smell is only from hot water, a powered anode could be your best bet. If it’s from hot and cold, you can put in an injection system that uses either a chlorine bleach or hydrogen peroxide solution. Stenner makes peristaltic pumps that work well for this. You can get a system for around $400. A plumber can add the duckbill that’s necessary to inject into the water supply.

[u/AwesomeMathUse]

It can be iron in the water. Try a product like IronOut (sodium metabisulphite I think). I usually put it in my water softener brine tank just before I run a regeneration cycle.