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Grey/smelly hot water

30489 Views 15 Replies 10 Participants Last post by  SPS-1
I'm a 29 year old first time homeowner. I recently bought a 14 year old home on 5.35 acres in southwestern Illinois. I am on a well/septic, and have had a few plumbing problems.

I am somewhat handy, and know enough to be dangerous. I recently replaced my propane water heater myself, so I no longer am taking cold showers. However, my hot water seems to have a grey tint to it, and smells.

I searched and found a thread:

That didn't address my problem exactly. I suspect my anode rod may need replaced. As far as I know, I am only on a small filter on my side of the well pump. I have no softener, and the problem is limited to the hot water.

From what I have gathered, bacteria in the water heater are causing the color and sulfur dioxide smell which makes my hot water unpleasant. Does this sound like a correct assessment to you, and the anode rod replacement will fix it?
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It does sound like a possibilty but you wouldnt normally think about having to replace anode rods on a new HWH. But if your well is producing high iron content water the anodes do convert the iron to sulfur dioxide and produce some pretty vile smelling water. Take a sample of your water to your local county ag. agent or to the health department and get an analysis. You may have to invest in some form of water treatment to cure the problem. I am no pro in that department so hopefully another reader will chime in and help us on this one.
You have bacteria in your well and you need to shock it. Simply pour 1 or 2 gallons of bleach down the well head and let it set for 3-4 hrs then turn on an outside hydrant and let it run untill you get the smell of bleach then let this set for 24 hrs. After 24 hrs turn on the outside hydrant and let it flow until the smell is gone. This should get rid of the smell.

Color is another issue. If it is black more than likely it is the bacteria in the well. It could also be the well itself if it is an old well that is lined in steel or an old jack pump that is steel as well

Start with the bleach and work from there. On my well I have to put a gallon of bleach down the well every other month.

I would also suggest that when the water enters your house it run through a sediment filter then a carbon filter and then a UV light.

What this does is seperate the sediment, then carbon for taste and the UV to kill any bacteria. We don't drink well water but cook with it and bathe. We have a RO system and that is for drinking.

I would cation you on adding a softening system until you have a water test. We are in the Dakota Aquifer some of my neighbors water is hard but mine is not. Just a cheap test so that you don't waste alot of money an a not needed softner.
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Thanks for the replies. I'll plan on pouring down a gallon of regular Clorox down the hatch asap. I'm guessing the existing bacteria in the water heater will die off. I'll let you know how it goes.

Shocking the well will kill the bacteria there now and as soon as the chlorine is gone, new bacteria comes in with the water recovering the well and you're all but back where you started except, some bacteria were not killed' because they produced slime that now hardens and then chlorine can't penetrate it. So you've made things a bit worse but in short time your odor is back in the hot water.

So turn the temp up on the heater to 140f for a few hours or overnight and kill'em that way. Then turn it down until the odor comes back. The bacteria is a group of harmless sulfate reducing bacteria. Or buy water treatment like a chlorination system or remove the rod and void the warranty or replace it with a different type that may not solve the problem. Those are the choices. Well, other than living with it.

And anyone that doubts it is a bacteria, the increased temp kill the bacteria and proves it is caused by a life form in the water.
I've replaced the anode rod with an aluminum one. the water was still gross so I drained the tank, put 8 cups of bleach in it (per water heater manufacturer's recommendation), and am not waiting with hopes that this will take care of the problem. With my symptoms always isolated to the hot water, it's apparent that my well itself is fine.
bacteria MAY still be coming from the well. so dont be too overjoyed yet. I use to live where it was impossible to have coffee(didnt drink it anyway) tea or any booze mixed with water,,turned to rotten egg smell and a VERY dark black color. Shower walls also turned deep dark brown in a couple weeks to a month tops. I used alot of muraic acid cleaning that crap off to keep it decent enough to 'use' I forget what we had in that well,,,think it was manganese but not sure.

neighbior didnt have it because he was a well driller and went way far deeper. if you live in a river vally around here it almost guarenteed to be same way(here)

Lots of different reasons for bad water both hot and cold,,,get it tested,its the only way,,and if its high in certain things like selinium,or other foreign contaminants like nitrates,find alternate sources or go reverse osmosis IF it will actually help!!
I've replaced the anode rod with an aluminum one. the water was still gross so I drained the tank, put 8 cups of bleach in it (per water heater manufacturer's recommendation), and am not waiting with hopes that this will take care of the problem. With my symptoms always isolated to the hot water, it's apparent that my well itself is fine.
I guess ya didn't believe me... you should read my previous post again.

The bacteria (SRB) live in the ground and groundwater) and in time the odor will return because the the bacteria will colonize the heater again. They thrive in like 120f water.

Turning up the temp to 140f for a couple hours kills them and prevents the odor. Until it returns if you turn it back down. It also protects you against Legionella bacteria which is quite dangerous if you were to have it in your water. That's a lot easier than adding bleach to the water heater right?
I did believe you. I understand the bacteria issue, but if you had seen the water from the wh you would see there is a problem. the cold water was fine, and after cleaning out the wh and bleaching it, the hot water is now good again.

I will be looking at shocking my well itself once I better understand the parts that go into it. I do appreciate your feedback and meant no disrespect by doing just the wh now.

I also turnined up the temp overnight at your direction. The water was still grey and funky so I chlorinated it (8 cups in a 40g tank).
Gray water in many cases, if not H2S gas coming out of aerated and depressurized water, is caused by little air bubbles in highly aerated water. Aeration is done by the faucet tip aerator.

Draining and then flushing a water heater should be done on an annual basis.

The higher temp thing was to kill the bacteria and get rid of the odor, and I'm sure you would agree it is much easier than finding a means to add bleach to the heater.
Sulfar smell on hot water

Ok I have been reading and reading about this issue . And it seams my case is not solved by the most obvious fixes. I have lived at this property for 45 years, but last year I had to drill a new well the first went dry. We have 2 houses on property one with conventional water heater very old at least 25 plus years powered by electric , the other house had hot water heated by oil furnace. The well was purified after installation and tested bacteria free several times.

6 months after new well. First water heater went bad and was replaced, within a few months it had sulfar smell . We tested the well water and came back no bacteria , no sulfar etc. It was in hot water only. Very high mineral content. We sumized the old rod had long ago wasted away and the old water heater just did not produce the smell. First we shocked the new tank with bleach and it corrected issue for a few months. Also want to note water temp is 150 degrees above the recommended 140 degrees. Rod was not replaced since installation is very hard would take many hours of labor cost to remove and get to it.

Then The other house got a conventional water heater and again within a month had the smell also. When that happened we changed the anode rod with one recommended by manufacturer to correct issue and shocked the tank using peroxide this time hearing it was safer .We also tested well water a 2nd time came back free of bacteria. It worked for about 4 weeks.
Now its back again .
The plumber wants to install a ultraviolet sterilizer on the water line. He says even though the bacteria was not found in water test it has to be bacteria causing this. But we have water temp coming out at over 150 degrees. My logic says that will not help.

Please give any advice. For now we just keep shocking the tanks until we can find a better solution. May also go back to oil furnace heat of water on one house. But need to fix the other tank .

Is the level of bacteria needed to cause this very low and not detectable in standard tests by health department???
Thanks Bob
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Hi Wodin,

Maybe the suggestions I gave to RSCHLITZ in post #4 in this thread might apply to your problem:

Best regards,
Do a search on powered anode rods and you'll get your answer. Costly, but not sacrificial, so you won't ever have to replace it. Don't waste your money (like I did) on a new anode rods alum. or magnesium. If you have softened water the alum/zinc alloy won't work either. I have not yet used the powered anode. Only speaking from the HOURS AND HOURS of reading trying to solve the same issue here.

Good Luck
Hydrogen peroxide kills that bacteria better then chlorine. The sulphur producing bacteria is anaerobic and does not like oxygen rich environments.

read up
The bacteria responsible for the odor is sulfate reducing bacteria (SFR). It lives in the ground and comes in with the water and thrives in the water heater; nice and dark and warm with little water movement. They use an ion off the anode rod to create the odor and 'eat' sulfate in the water.

A UV light will not work well with any reducing type bacteria; iron, sulfate or manganese.

Chlorine or peroxide makes no difference, they both kill all types of bacteria. But bleach is less expensive and easier to find.
I am not a plumber, but if turning up the temp on the WH gets rid of the problem, why not just install a mixing valve after the water heater, and leave the water heater permanently at 150 degrees. Around here, the mixing valve is code. (But get one with adjustable temp to over 120 degrees out)
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