Mold in Whole House Water Filter? Do This!

Author: Jason Hollow - Published: 2022/10/20 - Updated: 2022/12/22

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There is no doubt that whole house water filters are very effective at providing clean water to your entire home, but they are not without issues.

Mold problems are not uncommon among them, for example. However, while mold can be an unpleasant problem, it isn’t difficult to remove. And if you are having mold problems with your whole house water filter, we’ve got you covered.

The goal of this article is to teach you the causes of mold growth in a whole house filtration system, how to eliminate it, and why mold needs to be removed in the first place.

So, here is our guide on mold in whole house water filters!


Solution for mold in cartridge-based whole house water filter:

  1. Turn off the water source, relieve the pressure, and detach all the filter housings.
  2. To clean the mold-infested areas, you can use white vinegar, unscented household bleach that is diluted in warm water, or baking soda mixed with water.
  3. If the mold infestation has affected the filter cartridges, replace them.

Solution for mold in tank-based whole house water filter:

  • Tank-Based water filters are more difficult to deal with as the filter media can’t be removed as easily to clean the inside of the tank. Consider hiring professional help to clean your system.
  • If you managed to remove the entire filter media, you should probably replace it.
  • You can clean all the mold-infested parts thoroughly with the same cleaning agents like white vinegar, any unscented household bleach diluted in warm water, or baking soda mixed with water.

What Factors Influence Mold Growth in Whole House Water Filters?

Mold is a fungus that grows naturally in dark and wet locations, like your plumbing system. Mold only needs a warm, dark habitat and a food source to develop, such as mineral build-up in your home’s pipes or the paper in your sediment filter cartridge. Furthermore, mold is more likely to grow if your whole house water filter is not cleaned regularly.[1]

Another source of mold could be your well. Mold can leak into your well water if the well cap is damaged.

How to Remove Mold

mold in whole house water filter thumbnail

To remove mold, you’ll need to use a cleaning solution such as vinegar or bleach to treat the affected areas, like your whole house water filter, pipes, or water heater.

Let’s look at how to clean each one:

Cleaning Your Whole House Water Filter

The best approach to clean a whole house filter will depend on whether mold is located in a filter housing or inside a media tank.

Filter Systems with Cartridges

If your whole house water filter is cartridge-based, simply remove the filter housings and use a cleaning solution to clean each of them. You have three choices as far as cleaning solutions go:

  • Bleach: Dilute unscented household bleach in warm water, and scrub the mold away using a sponge or brush.
  • White vinegar: Soak the housing in white vinegar or coat it with a spray bottle. Allow it to soak for 15 to 30 minutes. After that, rinse the housing.
  • Baking soda: In a spray bottle, combine ¼ tbsp baking soda with water and spray the solution in any moldy places. Allow it to sit for 10 minutes before gently scrubbing.

If any filter cartridges are affected as well, it’s best to replace them.

Filter Systems Using Tanks

Large media tanks are much more difficult to clean because the filter media cannot be easily removed from inside.

In this case, you should consider disposing off the entire filter media and adding a fresh load once you are done cleaning the tank’s inner parts.

Cleaning Mold from Water Heaters

If you have mold in your water pipes, you most likely have mold in your water heater.

  1. Turn off the electricity to your tank-based water heater.
  2. Drain its whole contents. You can do this by turning on your home’s hot water taps and running the water for 15 minutes (or 30 minutes for an 80-gallon tank).
  3. Remove the tank’s anode rod.
  4. Pour 1-3 liters of vinegar into the tank, depending on its size.
  5. Replace the anode rod.
  6. Fill the tank with water.
  7. Allow the solution to settle for 6 hours, then drain it.
  8. Once it’s all drained, refill the tank with water and reconnect it to a power supply.

Note that, cleaning a tank-based water heater may only work for minor mold problems. If the infestation is too severe, you may need to replace the entire tank.

How Do You Get Rid of Mold in Pipes?

Water pipes can be tough to clean, and because they are continually moist and dark, you will almost certainly be unable to prevent mold from developing indefinitely. You may, however, keep it under control by sanitizing your pipes:

Supply Lines

Pour a sanitizing solution down your main water supply and flush your cold water lines to clean the pipes. You can use chemicals, but we recommend using something less harsh, such as vinegar or chlorine.

Wastewater Lines

Some experts advise cleaning wastewater pipes once a month by pouring ½ cups of a sanitizing solution down the drain and allowing it to sit for one hour.

Then, flush with hot water from the faucet.

How to Keep Mold Out of Your Whole House Water Filter Going Forward

Installing additional water treatment that kills mold, such as a UV filter system, is the only sure way to prevent mold in your whole house water filter going forward.

However, by regularly cleaning all the parts of your filter and replacing the filter cartridges in a timely manner, you can prevent mold from growing there.

How to Detect Mold in Water

water glass with dirt

Aside from hiring a professional, you can test your water for mold yourself.

Purchasing a mold water test kit and following the provided instructions is usually the best way. They’ll be something like:

  1. Open the kit and add ten drops of water to the test plate with a pipette or a clean eye dropper.
  2. Put the lid on the Petri dish, tape it tight, and wrap it in foil.
  3. Allow the sample to remain at room temperature for five
  4. Gently lift the foil to check for mold growth. If there isn’t any, leave it for another two days and check again.
  5. Repeat the test on a new plate to validate the results if growth is detected.

The Different Mold Types in Water

Mold comes in a variety of forms, each with its own classification. The following list differentiates them based on their health effects:

  1. Pathogenic mold: Pathogenic mold can cause diseases and infections. Pathogenic molds are categorized as opportunistic pathogens because they can harm people with impaired or weakened immune systems. Infants, the elderly, and those with compromised immune systems are the most prevalent victims of pathogenic molds. Pathogenic mold can be killed with disinfectants.
  2. Allergenic mold: Allergy and asthma patients are particularly vulnerable to allergenic molds. Mold allergies cause a hypersensitive reaction, culminating in an intense inflammatory response in the respiratory system. Small amounts of allergenic mold usually do not affect people without allergies. Most allergenic molds may be eradicated with household disinfectants, but some require the help of a specialist.
  3. Toxic mold: Toxic mold creates mycotoxins, dangerous chemicals that can kill humans. Unlike allergic and pathogenic molds, toxic mold actively harms other living organisms. Toxic molds are among the most lethal substances on the planet. Mycotoxins can enter the body through eating, direct skin contact or inhalation. Depending on the individual, toxic mold can cause minor irritation or possibly long-term sickness. When it comes to toxic mold, hiring a professional to remove it and disposing of any contaminated materials is necessary.[2]

Differences Between Mold, Mildew and Algae

Algae are plant-like microorganisms, whereas mold and mildew are fungi. Mold and mildew favor damp conditions and darkness, but algae prefer sunlight and warm temperatures.

Mold and mildew look similar and thrive in comparable conditions but differ in color and texture. Mildew has milder colors and appears as flat, powdery specks. Mold, however, has darker hues and seems fuzzy and slimy.

Furthermore, while algae can develop in sunshine and water, mold needs organic material to exist and grow.

The distinctions also extend to how mold, mildew and algae affect your health. Although most algae are safe, certain varieties (such as blue-green algae) can create hazardous toxins.

Mold, however, is always a problem that must be addressed as soon as possible.

Mold in Water Causes Serious Health Issues

Drinking a few sips of moldy water is unlikely to affect you, as our stomach acid can easily eliminate most of the mold spores we swallow. However, prolonged exposure to moldy water and high levels of mold in your water may cause health problems.

Continued exposure to mold in drinking water can cause the following symptoms in the short term:

  • Headaches
  • Respiratory issues
  • Blurred eyesight
  • A sore throat
  • Red eyes
  • Rashes and discomfort on the skin
  • Allergic reactions
  • Nosebleeds

woman with headache

People with weakened immune systems or mold allergies should be especially cautious of mold in water.

If you continue to be exposed to mold, it could create major health problems. Long-term exposure to mold in drinking water can result in toxic mold syndrome, Legionnaires disease, mold allergies, organ damage, and asthma development.

If you’ve discovered mold traces in your water or fear it may contain mold, you should analyze it to determine the level of contamination.


It’s understandable that you feel concerned about mold in your water supply.

After all, mold can lead to a lot of nasty health problems that nobody wants to have.

Mold could be growing in your pipes, or coming from your well, which means you’ll have to use a different approach depending on the situation.

One way to deal with mold in your pipes is by using a vinegar solution to clean them. Alternatively, you can install a water purifier that specifically targets mold, like a UV filter system.

Further Reading


Meet Jason Hollow

Jason Hollow Jason is the founder of Water Masterz and head of content creation. After six years in the industry, he has tremendous knowledge and first-hand experience on all things related to water treatment.

His credo: Not a single American should have to drink unhealthy water at home.

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