Pink Mold In Humidifier – Is It Dangerous? How To Prevent It

Last Updated on: 5th September 2023, 05:58 pm

Humidifiers are essential household appliances that come in handy when you feel like the air is getting dry and uncomfortable. They bring your indoor humidity levels back to normal and relieve congestion, coughs, dry skin, and many other dry air symptoms.

Humidifier mold is no fun!

However, many people tend to neglect the importance of regular cleaning and maintenance of their humidifiers which may lead to many problems such as pink mold. Read this Article to gain more knowledge on how can a humidifier cause mold.

If you’re one of those, you might have noticed a slimy layer of pink mold or residue on the sides or bottoms of your water tank. If so, you’ll need to eliminate this pink stuff from your device before it puts your health at risk.

This post will walk you through the facts that what pink mold in humidifiers is, how it forms, and what you can do to eliminate it. You’ll also find some useful tips to prevent this from happening.

Table of Contents

What is Pink Mold in My Humidifier?

pink mold in humidifier

You can see fungus or mold growth in various colors such as brown, purple, red, white, orange, or green. However, the most common type of mold found in your humidifier is pink mold. Although it looks like mold, it is a water-borne bacteria that thrive in your humidifier’s dark and humid environment.

Three types of pink mold include:

Serratia marcescens

Serratia marcescens also known as “pink mold” is, in fact, a common strain of bacteria that resembles mold. It can be seen in orange to pink colors and can be found growing in your laundry, kitchen, and especially in the showers or tubs of your bathroom.

This microorganism grows in areas that are prone to dampness and they usually feed on shampoo or soap residues in your bathroom and kitchen. You can remove this slimy substance easily by washing and scrubbing away the surfaces of your bathroom showers, sinks, and tubs regularly.


It is not common to find this type of mold in your home. The reason is that Fusarium mold usually infects plants and feeds on organic or plant materials.

Aureobasidium pullulans

It’s a type of mold that begins growing as a white or yellow color and then turns into a pink substance. It is commonly seen growing in bathrooms but it also feeds on organic substances such as wood or plants.

Now, you might be wondering which type of pink mold is growing in your humidifier. A. pullulans is likely the culprit behind the nasty pink residue found in your humidifier.

How Does This Pink Mold Form In My Humidifier?

A mist humidifier works by drawing water out of the water reservoir and dispersing this water in the form of fine mist. The dark and damp conditions of the inner chambers and the reservoir of your humidifier make a perfect place for these microbes to grow.

Even if you maintain your device, it is hard to stop this mold from growing. Pink mold usually starts forming colonies within 24 to 48 hours.

It is a good a sign that you haven’t maintained the appliance correctly.

The Role of Humidity Levels in Mold Growth

Maintaining optimal humidity levels in your home is crucial for preventing mold growth, including pink mold. Mold thrives in moist environments, and high humidity can create ideal conditions for its growth. Understanding the ideal humidity range and implementing measures to control it can help keep your home mold-free.

Optimal Humidity Levels

The ideal indoor humidity level for preventing mold growth is between 30% and 50%. At these levels, the environment is less conducive to mold growth, and it is more difficult for mold spores to multiply.

How to Eliminate Pink Mold From My Humidifier?

Removing pink mold from your humidifier isn’t rocket science. You can easily get rid of this slimy stuff present in your device by following a few simple steps. However, always follow the manufacturer’s instructions when you do the cleaning and mold removal process.

pink mold in humidifier

Things you’ll need:

  • Gloves
  • White vinegar
  • Chlorine bleach or hydrogen peroxide
  • Distilled or filtered water
  • Brush or sponge
  • Clean cloth

Here is how to clean pink residue from your humidifier:

  • Unplug your device from the power socket and carefully remove the water tank from the base of your humidifier.
  • Now fill the water tank with either bleach or hydrogen peroxide. You also can clean it with a vinegar solution.
  • Let this solution remain in the water tank for about 30 minutes. This will help break down the slimy substance that will be removed easily.
  • After 30 minutes, empty the water tank, rinse it thoroughly with warm water, and allow it to dry.
  • Using the vinegar or hydrogen peroxide solution mixed with water, clean the base of your humidifier. You can clean it using a clean cloth or a sponge to scrub away the pink buildup.
  • Remove mold from the vapor spout in the same way but this time, use a brush to get rid of pink mold from the small opening.
  • Clean the exterior parts of your humidifier by wiping the surface with clean water.
  • Make sure your humidifier is completely dry before you reassemble it.

Regular cleaning of your humidifier may help prevent the buildup of pink mold. Thus it ensures a healthy and safe environment.

Tips to Prevent Pink Mold or Residue in Your Humidifier

Fortunately, there are some preventative measures that you can take to prevent the formation of this pink mold. These include:

Use Distilled or Demineralized Water

It is suggested to use distilled or demineralized water in your reservoir instead of tap water. The reason is that tap water contains mineral deposits such as calcium deposits and magnesium. This mineral deposit favors pink mold growth in your humidifier. So, using distilled water may help stop formation.

Refill the Water Tank Daily

You should replace the old water in your tank with clean water every day so that the water doesn’t remain stagnant in your humidifier for a long time. This helps prevent mineral buildup and pink mold growth.

Regular Cleaning and Maintenance

Make a habit of regularly cleaning your humidifier at least once a week. Rinse the unit with lukewarm water. Don’t use chemical cleaning agents too often as they may damage your humidifier. Let the unit dry completely before you use it again.

Use Disinfectants or Humidifier Tablets

You can apply effective cleaning agents to eliminate pink mold growth in your humidifier. Humidifier tablets are also available that are specially made for this purpose. They control bacteria, pink mold, or scale buildup in your humidifier.

pink mold in humidifier

Use Tea Tree Oil

Tea tree oil acts as a natural disinfectant that can be used to kill pink mold in your humidifier. Tea tree oil can also be used as a decongestant that clears the airways and improves breathing for people who have respiratory problems. As tea tree oil is a natural product, it doesn’t damage your device, unlike other chemical agents.

Is Pink Residue In Humidifier Dangerous And Make You Sick?

Although pink mold is not as harmful as black mold, it can still pose health problems if exposed for a longer time. If your humidifier is not properly maintained or if you’ve not cleaned it for a long time, the pink mold exposure will likely spread into the air through water vapors.

Once in the atmosphere, these microbes can easily find their way to infect your body and cause infections. Long-term exposure may cause allergy symptoms such as coughing, sneezing, or wheezing.

People who have preexisting respiratory conditions are more prone to infections. Pink mold can lead to “humidifier lung” which is a condition caused by breathing contaminated air from the humidifier. The symptoms include cough, fever, and dyspnea.

Apart from respiratory illnesses, pink residue in humidifiers may also cause gastrointestinal and urinary infections. If you notice any of these symptoms or issues, know that it is time to get rid of that harmful stuff from your humidifier. It may also cause something known as hypersensitivity pneumonitis.

Look here for 10 warning signs of mold toxicity.

Different Types of Humidifiers and Their Susceptibility to Pink Mold

There are various types of humidifiers available in the market, each with its own set of advantages and disadvantages. The main types of humidifiers include ultrasonic, evaporative, and warm mist. Understanding the differences between these types and their susceptibility to pink mold growth is essential for proper maintenance and prevention.

  • Ultrasonic Humidifiers – The water in ultrasonic humidifiers can quickly become stagnant if not replaced regularly, creating a breeding ground for pink mold and other bacteria. To prevent mold growth in ultrasonic humidifiers, it’s essential to empty and clean the water tank daily and use distilled or demineralized water.
  • Evaporative Humidifiers – These humidifiers are self-regulating, as they release moisture only when the air is dry. However, the damp wick or filter can become a breeding ground for pink mold and other microorganisms if not cleaned and replaced regularly.
  • Warm Mist Humidifiers – The warm, moist environment inside the humidifier can be conducive to pink mold growth. Additionally, since warm mist humidifiers have a heating element, they may require more frequent cleaning and descaling to remove mineral deposits that can promote mold growth.


Pink mold in your humidifier may cause health issues if left untreated. So, it is necessary to regularly clean your device and take important preventive measures to stop or eliminate pink mold growth from your humidifier.

It is advised to clean the humidifier thoroughly at least once a week using effective cleaning agents. Using distilled water instead of tap water may also help prevent pink mold formation. Adopting a good cleaning schedule and following the important measures mentioned above ensures that you breathe safe and healthy air.