You scrub, you polish, and you scour, but every few weeks, you notice a slimy pink stain on your bathroom surfaces. And the really weird thing? It seems to show up just about anywhere you can think to look – around your sink basin, in your toilet bowl, ringed around your shower drain, or clinging to the bottom of your shower curtain.

What’s behind these mysterious pink rings, and what can you do stop them from forming?

The first part of the question is the easiest to answer. While some pink stains are caused by overly-metallic water, the most common cause of the colorful, slimy stuff is Serratia Marcescens.

What is Serratia Marcescens?

Serratia Marcescens is an extremely common type of bacteria, found in everything from soil, to food, to animals. Known for its pinkish-red pigment, Serratia thrives in moist or dusty conditions, and needs almost nothing to survive. Easily carried by air, Serratia bacteria seek out moist locations in which to grow.

Once they’ve settled in a damp spot, such as your bathroom, Serratia has everything necessary to thrive – standing water, open air, and the consistent introduction of phosphates and fats thanks to the soaps, gels, shampoos, and human waste products that filter through your bathroom every day.

While many homeowners fear that the presence of pink residue means that there’s something toxic in their water, the problems posed by the bacteria are mostly cosmetic; in small quantities, Serratia Marcescens is generally thought to be largely harmless to most healthy individuals, though we should note that it has been linked to some infections, including urinary tract infections and pneumonia.

How Do I Get Rid of the Pink Residue in My Bathroom?

Once pink slime has left its grimy mark, you can clean it away with just about any bathroom cleaning solution. We recommend trying a solution of one-part vinegar and one-part water; spray this mixture over the afflicted area and then scrub away with a soft bristle brush. For heavier or more set-in stains, chlorine bleach is usually a surefire way to clean away Serratia.

The thing about this particular stain, however, is that it always seems to crop up again and again. In this case, the best defense is a good offense. Get in the habit of drying your sinks and showers after every use with a rag or squeegee; preventing water from pooling is the best way to prevent Serratia from thriving.

In addition to getting rid of standing water, be sure to clean all of your bathroom surfaces – including your toilet bowl – regularly. Without grime, waste, and soap scum to feed on, your Serratia will be harder-pressed to grow into a visible problem.

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And for service or expert advice, day or night, be sure to drop us a line. Our experienced team is always here and happy to help!