Solved! How to Get Rid of Pink Mold in the Shower for Good
Noticed some unusual discoloration on your bathroom surfaces? Send unsightly pink mold packing with these tips for removal and prevention.
Q: I was alarmed to find pink mold in shower grout of the guest bathroom recently. Is this as bad as the toxic black variety? And, if so, how do I get rid of it?
A: Unlike run-of-the-mill green molds like Cladosporium, or the infamous toxic black mold, Stachybotrys chartarum, the pink “mold” in your shower isn’t actually mold at all. The discoloration comes from a biofilm—that is, a bacterial colony—of Serratia marcescens. The airborne bacterial species thrives in moist environments like showers, where it feeds on mineral deposits in soap scum and fatty deposits in soap and shampoo residue.
While it’s harmless to most healthy people whose skin may brush up against the pink mold in a narrow shower, it can cause various ailments (e.g. urinary tract or bladder infections) if it enters the body through the eyes or open wounds. The severity and variety of these ailments increases in individuals with compromised immune systems. Better safe than sorry: It’s best to remove the biofilm before the bacteria multiply and your exposure to it increases.
Fortunately, the light pink to dark red coloring (a result of the pigment the bacteria produces) makes it easy to spot and remove from shower, walls, floors, countertops, shower doors, and curtain liners. Using basic household cleaners and the techniques ahead, you can get rid of pink mold on hard and soft shower surfaces and keep it from coming back.
Scrub the biofilm off of hard shower surfaces. The stubborn biofilm of Serratia marcescens can only be removed through agitation and elbow grease. Start by mixing up a slightly runny paste consisting of a quarter-cup baking soda and a tablespoon of liquid dish soap in a small bowl. Suit up in gloves, protective glasses, and a respirator to limit your exposure to the bacteria, then dip the bristles of a soft-bristle scrub brush into the prepared paste and vigorously scrub down any visible patches of biofilm on hard surfaces in the shower (e.g. countertops, shower chairs, doors, and tile and grout lines on walls and floors). This process should loosen and lift the biofilm.
When you’re finished scrubbing, rinse away any loosened biofilm in the shower by either wiping down the scrubbed areas with a wet towel or turning on and detaching the showerhead to flush the slime down the drain.
Disinfect these same shower surfaces. It’s not enough to simply scrub away the color; you need to disinfect the surface to remove any lingering bacteria to prevent its return. Bleach is your best bet since it does double-duty to kill the last of the bacteria and dissolve stubborn stains left in its wake. Pour six ounces each of chlorine bleach powder and warm water into a 12-ounce spray bottle, then replace the cap and gently shake the bottle. Spray the solution directly over the hard surfaces of the shower you’ve scrubbed and let the solution dwell in the shower for 10 minutes. Then use a fresh soft-bristle scrub brush to lightly scrub down the sprayed areas, rinse once more, and dry the shower surfaces with a clean towel or squeegee.
Sanitize shower curtains. Shower curtains are a popular hangout for pink mold since they’re seldom cleaned and usually riddled with soap and shampoo residue. Running your pink-tinged curtain through the washing machine on a gentle wash cycle with warm water effectively removes Serratia marcescens bacteria and any associated stains. Be sure to first check the care label of your curtain to ensure that it’s machine-washable, then air-dry the curtain outdoors on a sunny day before re-hanging it in the shower.
Keep biofilm at bay. Pink mold is one stubborn biofilm that often reappears on hard and soft shower surfaces even after you’ve taken these outlined measures to remove it. Make your bathroom cleaning responsibilities easier on yourself by heeding these tips for preventing new biofilm from forming:
• Serratia marcescens is more likely to spread in damp areas, so towel-dry or squeegee the hard surfaces of your shower after every use to remove excess water.
• Use a water-dampened paper towel to wipe away soap or shampoo residue anywhere it collects in the shower after every use. Then, make a second pass over these areas with a dry paper towel.
• Remove soap scum from hard shower surfaces on a biweekly basis. Spray soap-scum-riddled areas of the shower with a 50-50 solution of white vinegar and warm water combined with one tablespoon of dish soap, and let the solution dwell for 15 minutes. Then scrub down the sprayed areas with a soft-bristle brush. Rinse away anything you’ve loosened from the tile and glass, and towel-dry or squeegee all wet surfaces.
• Machine-wash shower curtains, if you have them, on a monthly basis in a gentle cycle with warm water.
• Identify and repair leaking shower heads or faucets that may create excessive dampness in the shower.
• Turn on your bathroom’s exhaust fan before you shower and leave it on for 20 minutes afterward to help dry out air in the room. The pink stuff is more likely to spread when there is excess moisture in the air.
• Keep bathroom windows closed while you shower. Otherwise, being an airborne bacterial species, Serratia marcescens can waft into your bathroom from outdoors.