That pink or orange ring at the bottom of the shower tray, around the drain or on the sealant: almost everyone knows it. Just like the black dots in grout and silicone. They look alike, but they are two different things with the same cause: moisture and soap residue that stay put.
In short
- Pink or orange and slimy: usually a bacterium, often Serratia marcescens. It feeds on soap and skin residue.
- Black or grey-green in grout and sealant: mould. It grows where things stay damp for a long time.
- The fix: clean regularly, dry after showering and ventilate well.
- Never: mix bleach with vinegar or other acidic cleaners.
Pink residue: a bacterium, not mould
Pink residue is often called 'pink mould', but usually it is the bacterium Serratia marcescens. It is common in bathrooms and produces a reddish pigment, which is why you see it so clearly. The bacterium lives on soap, shampoo and skin oils and likes places that stay wet: corners of the shower tray, the drain, the bottom of the shampoo bottle and sealant edges.
For healthy people, pink residue is mainly unpleasant. Still, Serratia can cause infections in people with weakened immunity, for example in hospitals. All the more reason to simply scrub it away.
Black dots: mould
Black or grey-green dots in grout and on sealant are mould. Mould grows where it stays damp and the air is not refreshed. On tiles it wipes off easily. If it sits deep in the silicone, it often comes back; then new sealant is the only real solution.
How to clean it
- Pink residue: scrub with a bathroom cleaner or some washing-up liquid and a soft brush. Rinse with warm water and dry. Don't forget the bottom of bottles, the soap dish and the drain.
- Mould on sealant and grout: use a mould cleaner and follow the label. Wear gloves and turn on the ventilation.
- Shower head: include it in the clean. Residue easily clings to limescale and soap around the nozzles. How to descale it: vinegar or citric acid?
Note: never mix bleach with vinegar, citric acid or other acidic products, such as many descalers and toilet cleaners. Toxic chlorine gas can be released. Use them separately, rinse well in between and make sure there is fresh air.
How to stop it coming back
- Rinse. Rinse soap and shampoo residue off the walls and floor after showering.
- Dry. Squeegee the walls and floor dry. That also helps against limescale spots; see a limescale-free shower screen.
- Ventilate. Set the extractor to its highest setting while showering and let it run for at least fifteen minutes afterwards.
- Get bottles off the floor. Put them on a rack so the bottoms can dry.
- Clean the drain regularly. Hair and soap residue in the drain are food for bacteria. See shower drain smells or drains slowly.
Does a shower filter help against pink residue?
No. Pink residue and mould are caused by moisture and soap residue, not by your tap water. A shower filter doesn't change that; cleaning, drying and ventilating do. What a filter does and doesn't do is explained in shower filter: worth it or not?
What does help: a shower head that stays easy to clean. All Besjaar shower heads, such as the Besjaar Luxury Hand Shower, have silicone nozzles you can rub limescale off with a finger.
Frequently asked questions
Is pink residue in the shower dangerous?
Usually not for healthy people; it is mainly unpleasant. People with weakened immunity are more sensitive to it. So clean it regularly.
Why does pink residue keep coming back?
The bacterium is found all over the home and grows back as long as soap residue and moisture remain. Rinsing, drying and ventilating help most.
Can I use bleach and vinegar together?
No. Bleach combined with an acidic product can release toxic chlorine gas. Never use them at the same time.
Besjaar makes shower heads and filters for Dutch bathrooms, from Assen. Better water, every day.