Sulfur Smell in water
Treating Sulfur Odor and Yellow Water
One reader recently reached out asking how to remove a persistent sulfur smell and yellow discoloration from their water. A water test revealed that the water was acidic and high in minerals.
Unfortunately, there's no single system that can completely purify this type of water. However, using multiple systems together can effectively treat the sulfur smell and related issues. The most effective setup includes:
- Chlorinator
- Contact Tank
- Neutralizer
- Pro-OX Iron Filter
- Carbon Filter
These systems work together to eliminate odors, neutralize acidity, and remove iron and manganese from the water. They’re also low-maintenance—there are no cartridges to replace, and you only need to add about a gallon of chlorine bleach to the solution tank every 1–3 months.
Before beginning treatment, we strongly recommend performing a complete water analysis. This will help confirm whether your water contains hydrogen sulfide, iron, manganese, or other contaminants that contribute to discoloration and odor.
With the setup mentioned above, you’ll enjoy clean, odor-free, and iron-free water without affecting the hardness of your water. If desired, a softener can be added as an additional step.
Continue reading to discover more about each of these systems and how they collaborate to eliminate sulfur odors in your water.
Introduction to the Problem
A sulfur smell in water—often described as a rotten egg odor—is a common issue that affects many households. This unpleasant smell typically comes from hydrogen sulfide gas, which is produced by sulfur bacteria. These bacteria thrive in low-oxygen environments and release the gas as a byproduct.
Hydrogen sulfide levels can vary from barely noticeable to extremely strong. Whether the odor is faint or overwhelming, it’s important to identify and resolve the issue quickly to maintain safe, high-quality water in your home.
Causes of the Smell
The most common cause of a sulfur smell in water is hydrogen sulfide gas, which is generated by sulfur bacteria. These bacteria live in places like:
- Water heaters
- Well systems
- Plumbing and irrigation lines
They feed on sulfur compounds and release hydrogen sulfide, which gives off the telltale rotten egg odor.
Other possible causes include:
- Corrosion in the water heater tank
- Natural gas leaks
- Chemical reactions between water and plumbing materials
- Sulfur-containing odorants from natural sources
In some cases, metals in the plumbing system can amplify your sensitivity to the smell, making it even more noticeable.
Effects of the Smell
A sulfur smell in water isn’t just unpleasant—it can lead to real problems. It may:
- Make water taste and smell bad
- Affect the flavor of food and drinks
- Lead to gastrointestinal issues if bacteria are present
- Indicate corrosion or larger plumbing problems
In high concentrations, hydrogen sulfide gas can even be hazardous to humans and pets. The odor might also suggest the presence of other contaminants. That’s why it’s critical to address the issue promptly and thoroughly.
Testing the Water
To find the cause of the sulfur smell, start by testing your water. You can:
- Use an at-home test kit for a quick diagnosis
- Send a water sample to a certified laboratory for a more detailed analysis
Testing can reveal the presence of hydrogen sulfide gas, sulfur bacteria, and other hidden contaminants. Once you know what you’re dealing with, a plumber or water treatment professional can help you determine the best course of action.
Identifying the Source
Knowing where the sulfur smell originates is key to solving the problem. Common sources include:
- The water heater (especially if it contains a magnesium anode rod)
- Well systems or well water contaminated with sulfur bacteria
- Household plumbing, where buildup may occur over time
Thorough testing and inspection will help pinpoint the source. Once identified, you can choose the right solution. A continuous chlorination system, for instance, can kill sulfur bacteria and oxidize hydrogen sulfide. A carbon filter may also help remove odors.
To prevent future issues, follow recommendations from the National Institutes of Health and the EPA regarding regular maintenance and testing.
Continuous Chlorination and the J-PRO-22 Pump Chlorinator System
Chlorine is a low-cost and safe method for eliminating odors and bacteria, and it effectively oxidizes iron, manganese, and other contaminants in water, allowing them to be filtered out.
Although there are other ways to eliminate microorganisms and odors in water, chlorination is the most commonly used because it is low-cost and effective.
The chlorinator can be adjusted to maintain very low chlorine levels in the household (similar to city water), or a low-cost carbon filter can be installed to remove any trace of chlorine tastes and odors.
Contact Tank
A contact tank provides optimal contact time after chlorine, soda ash, peroxide, or other water-treatment-grade chemicals have been injected into the water. Achieving maximum possible sensitivity to sulfur odors is crucial, as these smells often indicate potential hazards.
By using a contact tank, you’ll reduce the amount of solution needed and ensure that the solution being injected is thoroughly mixed and dissolved in the water. Prior to recent research, there was limited evidence for the role of metals in olfaction, which has now highlighted their importance in enhancing the sensitivity of olfactory receptors to sulfur compounds.
Our WellMate Contact Tanks are constructed with a seamless inner shell made of molded polyethylene, providing impact and corrosion resistance. The tanks are high-quality NSF/ANSI 61 certified tanks for drinking water. Inlet and outlet connections are 1-1/4” but can be reduced to 1” or ¾” if needed.
Calcite Neutralizer
A calcite neutralizer filter will neutralize the low pH (acidic water) and help eliminate the corrosive effects of the water. Olfactory receptors play a crucial role in detecting sulfur odors, which can be a concern in water treatment. The neutralizer filter comes with everything you need, including calcite and corosex media, as well as simple instructions. Any plumber or person familiar with basic plumbing can install them.
Unlike older-style neutralizers, our neutralizers utilize Vortech neutralizer tanks, which feature an advanced internal screen that eliminates the need for a gravel base and reduces the amount of water required for backwashing by 30%. A quick once-per-week backwash for 8 to 10 minutes is all it takes to keep the calcite media in good shape.
These neutralizers require little maintenance and are very easy to use. Once a year, add more calcite to the neutralizer tank through the top-fill plug. Most customers use 25 to 50 lbs. a year at a cost of approximately $50 per year.
PRO-OX Iron Filter
The Pro-OX Iron Filter is a powerful and effective system for removing iron and manganese from well water. Understanding odors and odor mixtures is crucial in the context of water treatment, particularly in detecting the strong odor of sulfur. This system automatically removes iron, manganese, and sediment without the use of filter cartridges or chemicals. The iron filter is easy to install by any plumber or person familiar with basic plumbing.
The Pro OX Iron Filter removes both dissolved and oxidized iron and manganese by using a special type of solid manganese oxide media, which traps the iron and then automatically backwashes out the trapped rust and sediment to drain.
The backwash lasts approximately 15 minutes and occurs automatically, typically every 2–3 days, in the middle of the night when no water is being used.
If you install a chlorinator as described above, you can backwash the Pro-OX filter media with a chlorine rinse, which will kill iron bacteria and can extend the life of the Pro-OX media for many years.
For waters containing “rotten egg odors” (hydrogen sulfide), a chlorine feed ahead of the Pro-OX filter can be used to eliminate the odor and maintain the Pro-OX media's effectiveness. And unlike other media, which may last only 3-5 years, Pro-OX media will last you for more than 10 years!
Carbon Filter Backwash Systems
Our Carbon Backwash Filter Systems remove chlorine, tastes, and odors at exceptionally high flow rates with little or no pressure drop. The metal effect makes sense in enhancing sensitivity to sulfur odors, which is crucial for detecting gas leaks. Unlike expensive carbon filter cartridges, the Carbon Backwash Filter Systems use a bed of high-grade activated carbon to filter out chlorine, chemicals, and sediment.
These systems automatically backwash and rinse the carbon media clean; there is no need to change short-lived filter cartridges, and no problems with pressure drop from clogged filters. The carbon media typically lasts 3–5 years and is easy to remove and replace. Detecting gas leaks through the recognition of sulfur's distinctive odor is essential for safety, as sulfur is intentionally added to natural gas for this purpose.
Finally, here is an illustration of a typical installation of these systems:
Also see: 7 Signs Your Water Well is in Trouble
Frequently Asked Questions (FAQs)
1. What causes the sulfur smell in well water?
The most common cause is hydrogen sulfide gas, which forms when sulfur-reducing bacteria break down sulfur compounds in low-oxygen environments like wells and water heaters. The gas produces a “rotten egg” odor that can be unpleasant and potentially harmful at high concentrations.
2. Is hydrogen sulfide in water harmful to my health?
At low levels, hydrogen sulfide is more of a nuisance than a health risk. However, high concentrations can cause nausea, headaches, or respiratory irritation. It’s also corrosive to plumbing and can damage appliances over time, so treatment is recommended.
3. How can I test for sulfur or hydrogen sulfide in my water?
You can use an at-home hydrogen sulfide test kit, or for more accurate results, send a water sample to a certified laboratory. A full water analysis is recommended to identify additional issues like iron, manganese, or low pH.
4. Will a standard water filter remove the sulfur smell?
Most standard carbon filters may reduce minor odors, but for strong sulfur smells, you’ll need a more advanced solution—such as chlorination followed by a contact tank, Pro-OX iron filter, or a carbon backwash system. These systems oxidize and remove the gas effectively.
5. How often should I maintain sulfur treatment systems?
Maintenance needs vary by system. Chlorinators require bleach refills every 1–3 months. Neutralizers typically need calcite added once a year. Backwashing filters like the Pro-OX and carbon systems should auto-clean every few days, with media replaced every 3–10 years depending on use.
