These stains are likely excess mold and or mildew.
Clean mold off rubber bath mat.
Finally i would give your mat a good soak in vinegar and water at least once every couple months with a good rinse afterward and hang to dry.
If you d rather not spend your bathroom cleaning time scrubbing mold and mildew from your bath mat be sure to hang it after each use.
Rubber bath mat mold and mildew removal.
So at first start the cleaning by removing the mold.
Hand wash bath mats that are not machine washable or to just extend the life of the mat bath.
How to remove bath mat stains from bathtub.
Mold is mainly responsible for creating stain the rubber bath mat.
Hand washing is gentler especially on.
Remove these bath tub stains by making a mixture of 1 cup white vinegar and 2 cups hot water.
Both vinegar and bleach are effective at killing mold.
It got the mold because you suctioned it to the wall leaving water trapped inside the cups a breeding ground in a humid bathroom.
Because rubber is porous the mold may penetrate the surface of the rubber.
Apply bleach on the water and let them.
Put on rubber gloves and pour a small capful of laundry soap in the water.
Bleach kills mold faster but may discolor or weaken the rubber.
We know that you have lots of questions about cleaning and we want to give you those answers.
When mold forms on rubber it s important to kill and remove it quickly to prevent long term damage.
Keep the mat on the floor and close the exit of the water.
Eventually this can cause the rubber to fall apart.
To eliminate mold or mildew leave the rubber bath mat in the diluted bleach solution for 3 4 hours.
Fill the bathroom with hot water and continue until the bath.
To freshen up the bath mat with a quick clean scrub the rubber bath mat with a cleaning brush or scouring pad to remove.
You might want to throw it away.
You can wash it in the washing machine cold or warm water please and don t put it in the dryer or you can use borax to clean and disinfect.
Mix it in a spray bottle and apply to the bath mat stain.
Place the bath mat in the sink or a large bucket of water.
This will help stay on top of any mildew or soap scum build up in turn preventing moldy bath mats.