What is that pink discoloration, is it water stain?

I clean my tub and sink often. But I notice if it isn't often enough, there's a pink stain around the tub and under mat.


This also appears on my white dish strainer in kitchen.





Is it a form of mold? Why is it pink?

What is that pink discoloration, is it water stain?
I know it is a form of mold....the easy one to remove from caulking.
Reply:Hello, if you have well water what you are seeing are iron residues, if you have city water there could be contaminates in the water, sometimes algae blooms get in there or it could be from your pipes if you have older plumbing.Hope this helps:-)
Reply:I always thought it was a rust stain, I use comet when it starts to show and it comes right off.
Reply:yes it is use bleach
Reply:You may have a slight amount of iron in the water. You can buy a water testing kit from the hardware store to test your water. If you have a Dollar General Store, they have a product called The Works, Tub and Tile Cleaner. There is also one for the toilet. I've used many products over the years, and this is the best product I have found to clean the tub. If you hang your mat on the side of the tub after showering it will allow the water to drip from it. The Works Tub cleaner will remove the discoloration, and take care of soap scum, etc. It's my #1 pick on tub cleaners.