When talking about molds, the first to come to mind is dark, icky marks. However, you might be surprised to know that molds actually come in various colors, including green, orange, purple, and even pink. Overall, there are 13 common mold colors – all of which are health-threatening. To ensure that your home is safe from the fungus, you should know how to prevent pink mold in humidifier and other moisture sources.
What is pink mold?

Like any mold species, pink mold thrives in moisture and darkness. The color pink to orange that you see is actually the spores that will spread once you disturb the surface.
Moreover, pink mold is a growth of the Serratia marcescens bacteria. While it looks like mold, this is actually a type of airborne bacteria.
Another pink mold is the Aureobasidium pullulans. This fungus has a mild light pink color that turns yellow to black as it ages.
Like the S. marcescens, A. pullulans also like moist surfaces with organic matter they can feed on. Most of the time, pink mold can be found in bathrooms, which appear as pink slime on the tile grout, toilet bowl, and shower. nYour humidifier is also one of the leading breeding grounds for pink molds.
The bacteria/fungus feed on soap scum and organic matter that came from the human body. Since they feed on organic matter, you can also find pink molds on linseed oil paint, wooden window frames, and even houseplants.
While there’s another pink mold called Fusarium, it’s not likely to be found in a household setting. Nevertheless, it can grow on house plants and creep to your carpeting.
So how come this specific mold is pink? The pinkish color of this mold is due to the room temperature to where it grew. And unlike mold growth, pink ones have a slimy consistency.
Health risks of pink mold
Pink isn’t as toxic as black molds, but it doesn’t mean it can’t you anymore. Those with sensitivities and allergies can still experience adverse reactions to pink mold if its growth isn’t managed.
To give you an idea, here are some of the health risks pink mold could bring:
- Bladder infections. Pink mold is known to cause bladder infections, specifically urinary tract infection (UTI), if not controlled. Nevertheless, this infection will only occur if the mold infestation in your home is massive and you’re also in bad health.
- Asthma attacks. Those with compromised respiratory systems will experience severe reactions when exposed to pink spores. It can lead to massive asthma attacks, recurring colds, and unexplained sickness within the family.
- Pneumonia. Those with weak lungs are susceptible to pneumonia when exposed to pink molds for long periods. The risk gets higher if the person lives an unhealthy lifestyle.
- Gastrointestinal trouble. If ingested, the pink spores can upset your stomach and result in diarrhea. For those who are heavily exposed to the pink molds, poisoning may even occur.
- Infected wounds. If you have an open wound, pink mold spores can make it infected and sore. The risk of contracting this problem increases because pink mold is often found in bathrooms and areas for cleaning.
- Eye infection. Take note that pink molds can also grow on contact lenses if you’re not careful. It’s because contact lenses have organic matter and moisture needed for pink mold to thrive. If you’re wearing contacts, it’s important to address immediate signs of pink mold infestation.
How to prevent pink mold in humidifier
It can be tricky to prevent mold, especially in humidifiers, since it’s a constant source of moisture. But to help reduce the occurrence of health-threatening molds, here are a few of my proven recommendations:
✔️Keep your humidifier clean.

The best and most effective way to avoid pink mold in your humidifier is to clean it regularly. Remember that the s. marcescens bacteria is airborne and can reach your dirty humidifier in no time. Here’s what you need to do to keep your humidifier pink mold-free:
- Unplug the humidifier and remove the reservoir.
- Fill the reservoir with equal parts of white vinegar and water. You can also use hydrogen peroxide if you don’t like the scent of white vinegar.
- Avoid using bleach as this can damage the humidifier material over time.
- Let the vinegar or peroxide sit in the humidifier reservoir for about 30 minutes. This will give the solution enough time to dislodge and neutralize the pink molds.
- After that, drain the reservoir and rinse it with running water. If there are still molds left, you can refill the tank with white vinegar and water, this time with more vinegar. You can also brush it with an old toothbrush.
- Once you’re done rinsing the reservoir, you should let it dry.
- You should also clean the humidifier base and inspect if the pink molds have infested other parts.
- If there’s pink mold in the hose and base, you can use the vinegar or peroxide solution to remove it.
I recommend cleaning your humidifier this way once a week. If your house is prone to molds, you can clean it twice a week or more. Just make sure that you let it dry first after each wash to avoid damaging the circuits.
✔️Consider using humidifier tablets.
Aside from cleaning your humidifiers, you can also use humidifier tablets to prevent pink molds. It also comes in sticks and drops form to suit your liking.
These humidifier add-ons are formulated to neutralize bacteria, molds, and other odor-causing growth.
For example, the PureGuardian Antimicrobial Aquastick is made to arrest humidifier molds. It can be used in both ultrasonic and evaporative humidifier types.
Each Aqua Stick is suitable for one liter of water. If you have a two-liter humidifier, you should use two sticks for optimal results.
Moreover, you need to replace the Aqua Stick every 90 days. But if you refill your humidifier often, I suggest that you replace the stick each month to prevent mold.
✔️Pick your houseplants wisely.
Pink molds can grow on houseplants, and the spores can transfer into your humidifier. With this, you should always use sterile soil to prevent any fungus or bacteria from entering your house.
Aside from that, you should avoid overwatering your plants. The excess moisture will allow pink molds to thrive since potted plants have enough organic matter to fuel mold growth. Remember, it’s better to underwater your plants than to overwater them.
✔️Monitor your home’s humidity
When using a humidifier, it’s crucial to monitor the relative humidity level of your house. This way, you’ll know when to turn off the humidifier. Remember that too much moisture in the air can fuel the proliferation of pink molds, specifically the airborne Serratia marcescens bacteria.
We always recommend using a hygrometer to monitor humidity levels in your house. Relative humidity higher than 55% to 60% is a sign that you need to rest your humidifier.
By doing this, you can avoid all types of mold from growing in your house.
✔️Use a dehumidifier
A home dehumidifier is an excellent pair with humidifiers as it balances the moisture level of your house. If pink molds are in your humidifier and everywhere in your house, a dehumidifier can help combat the infestation.
Moreover, the dehumidifier will deprive the pink mold spores of their much-needed moisture. However, you should also set a target relative humidity to prevent your dehumidifier from making the air too dry.
It’s also important to match the size of the dehumidifier to your home. Large homes or rooms need an equally large unit to remove excess moisture efficiently.
✔️Let the sunlight in
Natural sunlight is an indispensable solution in combatting pink molds before it gets into your humidifier. Opening a window and letting your room bask in the morning heat will save you from problems related to excessive moisture.
Aside from sunlight, this will also ventilate your room to allow moisture to evaporate naturally.
✔️Keep your bathroom dry and clean.

Although pink molds might be more common in humidifiers, you also have to target other potential sources of the spores. For example, your bathroom is one of the biggest breeding grounds for pink molds. Make sure that you clean your tile grout and toilet with a bleach solution to kill any present spores.
Moreover, you should also rinse any shampoo and soap scum on surfaces. This organic matter serves as food for the spores, which will trigger an infestation.
Aside from that, you should make it a habit to wipe your bathroom tiles and mirrors after each use. These surfaces cause condensation where stagnant moisture can cause pink mold growth.
✔️Clean up spills
You should never ignore minor spills that come from your humidifier. This small amount of moisture will get absorbed on fabrics, wood, and other porous materials. Over time, the moisture will harbor the growth of molds, which will transfer into your humidifier.
The same goes for spills on your laundry area, kitchen, and living room. You should also avoid wet umbrellas bundled on the floor. Always air out these items outdoors if possible.
✔️Consider replacing your humidifiers.
Humidifiers that are older than 5 to 10 years old are candidates for replacements. These old appliances are no longer efficient in releasing moisture. Also, it will be prone to pink molds due to the cracks and scratches that are hard to clean.
Aside from that, building parameters change over time. Your humidifier might be too old and no longer compliant with the said rules.
As for portable and cheap humidifiers, they will require frequent replacements, sometimes every 1 to 3 years.
Frequently Asked Questions
Q: What happens if you breathe in pink mold?
A: Breathing in pink mold can cause respiratory distress. It will cause coughing, allergies, asthma attacks, and severe irritation. Aside from that, the spores can also cause infection in your lungs and other organs if inhaled in large amounts for long periods.
Q: Is pink mold worse than black mold?
A: Pink mold is a lesser evil than black mold, but it’s still evil nonetheless. This mold can still make you sick if you don’t control it in your home. Depending on your sensitivity level, pink mold can trigger sickness similar to that of black mold.
Q: Why does my toilet have a pink ring?
A: The pink color on your toilet is pink mold. This is caused by the Serratia Marcescens bacteria, which can be harmful to one’s health when not controlled. And since you can see it on your toilet, the mold is likely present in other parts of your bathroom as well, like the tiled floor, walls, and sink.
Q: Will tap water cause pink mold in my humidifier?
A: It’s totally fine to use tap water in your cool mist humidifier. Just make sure that you clean the reservoir and hose before each use. This way, you can prevent mold, pink or not. But when in doubt, you can always use distilled water, especially if you have sensitive lungs.
Q: Does pink mold have spores?
A: Pink molds have spores, which allow the bacteria to spread all over your home. This is why molds can easily infest your entire home without you knowing it. So once you see it in your humidifier and other areas, you should clean it up right away.
Q: What happens if you touch pink molds with bare hands?
A: Touching pink molds won’t make you sick right away. However, you should avoid doing so if you have an open wound or skin infection on your hands. Also, you should wear gloves when cleaning humidifiers with pink mold to avoid contact with the spores.
Final words
Knowing how to prevent pink mold in humidifiers will save you from potential health risks the fungus brings. It’s crucial to keep your device clean and always monitor your home’s relative humidity and indoor air quality. This way, you can reduce the possibility of mold growth and other pathogens.
Do you have other tips to add to this post? Share it with us in the comment section!

Home Air Quality is founded by Bernard K to provide information on Indoor Air Quality in Homes and enlighten people about what they need to know about creating and maintaining a comfortable and healthy home environment.
We believe that “Quality air brings a healthy life.”