Hot Topic: Malodorous water in shower

June 12, 2012

POSTED Posted By leelundy on 3/7/2012 at 3:04:22 PM We have a customer where we have a backwashing pH filter followed by standard softener. System has been working great


Posted By leelundy on 3/7/2012 at 3:04:22 PM
We have a customer where we have a backwashing pH filter followed by standard softener. System has been working great for years but all of a sudden he got this rank odor in his shower. We traced it back to the water heater and the customer removed the anode completely, said it was very slimy. Smell went away for two weeks and now it has come back. We have shocked the well with tons of chlorine and the smell won”t leave. He doesn”t get the smell unless they take a very long shower. He has two water heaters, one feeds into the other one.


Gary Schreiber, CWS VI: 3/7/2012 6:18:02 PM
Cause is probably due to sulfate-reducing bacteria (SRB). Continuous chlorination of the well is the only fix. You also said they removed “the anode.” Did they remove it from both heaters?

Were the heaters also chlorinated afterwards? Was the softener disinfected? Was the house”s internal plumbing disinfected?

Remember, if you do continual chlorination, that you should also install a carbon filter before the softener to protect the resin.

Jim Wark: 3/7/2012 7:35:11 PM
I agree with Gary but would like to add: Put back anodes with a more noble metal. If this is done and you chlorinate the lines properly, the odor should stay away.

I always recommend to well users to disinfect by whatever means the incoming water supply. You never really know what is being introduced to the well.

Hopefully, they don”t have issues with iron or manganese. That would become a new topic.

leelundy: 3/8/2012 9:49:40 AM
The builder came back and replaced both anodes with aluminum. Then, we came out and shock chlorinated the well at a very high level of chlorine looping it back into the well via both the water heater drains. I did notice when I was doing this that the water would be clear and then muddy like chocolate milk so I disconnected the loop line from water heater drains and then connected to the faucet at the well tank. Same thing, spurts of muddy water.

Once we chlorinated the well we ran chlorine through the entire house. Customer said smell never went away. We shocked it on three different occasions and sanitized the softener.

At that point the customer had someone remove both anodes. Very little iron in the water from the tests we”ve done in the past. Is there a test for sulfate-reducing bacteria?

scruffy dee: 3/8/2012 1:31:54 PM
Is the smell like rotten eggs, fishy or?

leelundy: 3/8/2012 2:00:04 PM
The customer is reporting rotten egg/fishy smell. I have caught a small sniff of it and it tends to be fishy more than rotten egg smell. It”s only happening in the master bath shower and only on long showers. The son reports the smell sporadically.

We went out today and completed a service call. We saw the aluminum anodes the builder installed that the homeowner had removed. They had white powder on them and were pitted fairly well (less than six months old). Below is the water test.

Raw test:

  • 6.8 pH
  • .8 ppm Fe
  • 112 TDS
  • 4 TH
  • No odor


  • 7.0pH
  • 0 ppm Fe
  • 210 TDS
  • 1 TH
  • No odor

scruffy dee: 3/8/2012 5:24:32 PM
I was looking in books during my breaks and cannot add anything worthy other than maybe not enough contact time, possible biofilm, sludge, anaerobic conditions?

Gary Schreiber, CWS VI: 3/8/2012 6:33:33 PM
The test for SRB is called a BART analysis.

Taoward Lee: 3/9/2012 1:51:05 PM
Check to see if the water to the home/hot water is filtered with activated carbon which nullifies any incoming chlorine/chloramines. Without the continuous low level chlorine/chloramines for bacterial control, the chlorine shock treatment will diminish and the bacteria will eventually re-establish itself.

leelundy: 3/9/2012 1:57:07 PM
No carbon anywhere in system. Just a b/w pH filter and softener.

Rex Johnson: 3/10/2012 7:46:15 PM
This is very puzzling. You say the system has been working well for “years” and suddenly your customer gets a rank odor in his shower. We all know water quality can change, but in our experience it does not usually happen in an instant.

I was also wondering why there is a pH enhancer since the pH of the water is 6.8. That”s not all that far from a true neutral of 7.0 and we have never had an issue with a conditioner working just fine at a pH of 6.8. Perhaps there is a medical issue.

Anyhow, you mention that you tracked the odor to the hot water side of the home. Rods were cut out, replaced and cut out again. You super-chlorinated the well and the premises. Yet, the odor remains. Very unusual.

Then you say that the odor is only in the master bath shower and only on long showers. Even more unusual.

Our experience with sacrificial rods/mag rods/anode rods is that once it has been removed, the well and the house disinfected and no carbon at all in the system, all should be fine.

If there were problems with either the enhancer or the softener one would expect the issue to be duplicated everywhere in the home. It may be but just not as evident as it is in the master bathroom.

Taking long, hot showers will exacerbate any issue since the area is confined and the length of time water is running is more pronounced. My guess is that the issue is not limited to the master bath but is, in fact, home-wide. The other areas have better ventilation, shorter consumption times and less opportunity to even think about the issue.

Still, it makes no sense to me at all. Anytime we have ever performed the work that you have done, the rods removed, changed and blasted with chlorine bleach, that problem was solved.

Just out of curiosity, have you placed both the pH enhancer and softener into bypass for any period of time to see what might happen? Just wondering if there may be growth in either of those media tanks (which should have been placed into bypass during the super chlorination) which enters the home and is then found only in the master bathroom.

Wish there was more but you have done everything we would have done to address the problem. Again, I can”t make any sense out of it.

billblack: 3/12/2012 10:21:20 AM
We often find that when there is only one location with smelly water, it isn”t the water. Is there a way when the water smells bad to take a sample outside the shower and see if it smells, there? It may be that some odor is coming from the drain. We”ve had countless people who”ve had an odor in their water only when brushing their teeth — they are bending over the drain. Also, often in sinks, there may be supply line issues, but that”s not likely in a shower.

leelundy: 3/13/2012 10:37:37 AM
One of the first areas we looked at was the drains. We had the homeowner pour chlorine down the drain. We also advised that the vents on top of the house be checked for obstructions and possible smoke tests be run.

The pH was originally 5.5 five years ago when we installed the system which is why the pH filter is in place. We tend to have fluctuations in the pH over time in this particular area. All other water tests stay constant, such as iron, hardness and TDS. We have had the system on bypass for at least one week with the same complaint of smell.

The homeowner says his son also has some odors in his showers but not very often. I have a SRB test on the way to determine if it”s present.

One time I was able to get a slight smell at the kitchen sink. It was so slight that I could not get a clear idea if I had to describe it I would say it was more fishy than sulfur.

One of the good things about the water business is no two days are alike.

rjh2o: 3/13/2012 9:40:17 PM
Depending on how the anode rods were removed there can still be smell coming from the water heaters.

Some water heaters will have more than one anode rod.

If there was a separate fitting for the anode rods and the rods were cutoff from the base of the fitting there is still some of the rod in the fitting and will cause the odors in hot water. Always use a brass plug to plug the anode rod hole.

If the anodes were on the hot water side and they were cutoff flush the same problem can occur.

If SRBs are the issue a sanitizer water conditioning system with KDF media and chlorine generator will solve the problem.

An electric anode rod may also solve the problem.

There may be residual material in the bottom of the water heater from old anode rods. Chlorinate water heater and flush from boiler drains at bottom of tank. Do not drain tank, flush with water. It may take several flushes to break up any sediment and flush from heaters.

scruffy dee: 3/28/2012 12:54:51 PM
Before you fade away into cyberspace, would you mind giving me a wrap up? What happened in the end?

leelundy: 3/29/2012 9:08:07 AM
The SRB test has finally been completed. No SRB detected after 10 days. While I was there I turned the water heaters up to 140 degrees and advised the homeowner of the change. We”ve heard from numerous homeowners that by turning up the temperature to 140 degrees they got rid of the smell in their water heaters. The customer reported no change in the smell.

The customer did say that when we chlorinated his well the last time the chlorine was very strong and then as soon as the chlorine smell left the odor was back. We actually looped the chlorine through the drains in the water heaters back into the well to get full strength chlorine in the water heaters. At this point I suspect a piece of the original magnesium anode rod is still in one of the water heaters. Maybe when the builder was removing it he dropped a piece by accident?

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