What Is Pink Mold in Your Shower and How Do You Get Rid of It?
The pink or pinkish orange slime in your shower is not actually mold. It is a bacteria called Serratia marcescens. It feeds on soap residue and thrives in warm, wet places. Clean it with hydrogen peroxide (not bleach), and prevent it by squeegeeing after every shower and running your exhaust fan for 20 minutes after you are done.
It is bacteria, not mold
That pink film coating your shower tiles, grout, curtain liner, and shampoo bottles is almost always Serratia marcescens. Despite the name "pink mold," it is technically a gram negative bacterium, not a fungus. This matters because the treatment is different.
Serratia marcescens produces a pigment called prodigiosin, which gives it that distinctive pinkish orange color. It is found naturally in soil and water. It ends up in your bathroom because your water supply carries trace amounts of it, and your shower provides the perfect conditions for it to multiply: warmth, moisture, and a steady food supply of soap scum, shampoo residue, and body oils.
The reason you see it most often in the shower, around the toilet waterline, and on the edges of your sink is that those are the places where standing water and organic residue meet warm air. It can appear within days of a deep cleaning if the conditions are right.
When pink is actually a real fungus
There is one exception. A yeast like fungus called Aureobasidium pullulans can also appear pink, especially in early growth stages. Aureobasidium is a true fungus and a real mold concern.
How to tell them apart: Serratia marcescens forms a smooth, slimy film. It wipes off easily with a finger. Aureobasidium starts pink or light colored but darkens to brown or black over time. It has a slightly textured or velvety surface and does not wipe away as easily.
If the pink growth in your shower is turning darker, is fuzzy or textured rather than slimy, or has been there for weeks and resists simple cleaning, it may be Aureobasidium or another true fungus. In that case, treat it like real mold: clean with hydrogen peroxide, ensure the area dries completely, and address the ventilation problem.
How to clean pink mold from your shower
What you need: A spray bottle with 3% hydrogen peroxide (the kind you buy at any drugstore), a stiff scrub brush, baking soda, rubber gloves, and eye protection.
Step 1: Spray hydrogen peroxide directly on all pink areas. Cover the grout, tile, glass, and any corners where the pink film has built up. Let it sit for 10 minutes. Do not rinse yet.
Step 2: For stubborn spots, make a paste of baking soda and hydrogen peroxide. Apply the paste to the grout lines and textured surfaces. Let it sit for another 10 minutes.
Step 3: Scrub everything with a stiff brush. Pay special attention to grout lines, the base of the shower, the drain area, and corners where the wall meets the floor or ceiling.
Step 4: Rinse thoroughly with hot water. Dry the surfaces with a towel or let the exhaust fan run until everything is dry.
Why not bleach? Bleach will remove the pink color, which makes it look clean. But bleach is less effective at actually killing Serratia marcescens bacteria compared to hydrogen peroxide. The pink comes back faster after bleach treatment. Hydrogen peroxide is an oxidizer that kills the bacteria at the cellular level without leaving behind moisture the way diluted bleach does.
How to prevent it from coming back
Squeegee after every shower. This is the single most effective thing you can do. Wiping down the walls, door, and tile removes the water and soap residue that Serratia feeds on. It takes 30 seconds and cuts your pink mold problem by 90%.
Run your exhaust fan during and for 20 minutes after showering. The fan removes humid air from the bathroom. If your fan is loud, weak, or nonexistent, that is likely why you have a persistent pink problem. A good bathroom fan should move at least 50 CFM (cubic feet per minute) for a standard bathroom. You should feel air being pulled when you hold a tissue near the fan grille.
Rinse the walls before you get out. A quick rinse with the showerhead knocks soap residue off the walls. Soap residue is the primary food source for Serratia. No food, no colony.
Wash your shower curtain liner monthly. Throw it in the washing machine with hot water and a cup of white vinegar. Shower curtain liners are one of the biggest Serratia breeding grounds in the bathroom.
Fix any dripping faucets or showerheads. A slow drip provides a constant source of moisture even when the shower is not in use. That is 24/7 growing conditions for bacteria.
Leave the bathroom door open after showering if you do not have a good exhaust fan. This allows humid air to dissipate into the rest of the house rather than sitting in the bathroom.
Health risks: who should worry?
For most healthy adults, Serratia marcescens in the shower is more of a nuisance than a health threat. It does not produce mycotoxins the way true molds like Stachybotrys or Aspergillus do.
However, Serratia marcescens is an opportunistic pathogen. That means it can cause infections in people whose immune systems are weakened. Specific risks include:
Urinary tract infections in catheterized or immunocompromised patients.
Wound infections if you have open cuts or scrapes and the bacteria enters the wound.
Respiratory infections in people with chronic lung conditions or suppressed immune systems.
Eye infections if contaminated water or contact lens solution touches the eyes.
If you are immunocompromised, elderly, have a chronic illness, or have young infants in the home, clean pink shower buildup promptly and keep the bathroom dry. For everyone else, it is a cosmetic problem that signals your bathroom needs better ventilation and drying habits.
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Get Early AccessFrequently Asked Questions
Is pink mold in the shower actually mold?
No. The pink or pinkish orange film you see in your shower is almost always Serratia marcescens, which is a type of bacteria, not a fungus or mold. It thrives in warm, moist environments and feeds on soap residue, shampoo, and body oils. It looks slimy and spreads in a film, unlike true mold which is usually fuzzy.
Should I use bleach to clean pink mold in the shower?
Hydrogen peroxide works better than bleach for Serratia marcescens. Spray 3% hydrogen peroxide on the pink areas, let it sit for 10 minutes, then scrub with a stiff brush. Bleach can remove the color temporarily but does not kill the bacteria as effectively. For stubborn buildup, make a paste with baking soda and hydrogen peroxide.
Is pink shower mold dangerous to your health?
For most healthy people, Serratia marcescens is a low health risk. It can cause urinary tract infections, wound infections, or respiratory problems in people with weakened immune systems. If you are immunocompromised, elderly, or have open wounds, take it more seriously and clean it promptly. It is not as dangerous as true mold species like Stachybotrys or Aspergillus.
How do I stop pink mold from coming back in my shower?
Squeegee the walls and door after every shower. Run your bathroom exhaust fan during and for at least 20 minutes after showering. Rinse soap residue off walls before you get out. Wash your shower curtain liner monthly. If your bathroom has no exhaust fan or window, consider installing one. Serratia feeds on moisture and soap residue, so removing both is the key.
