First off - I am quite certain this is NOT RUST. I am quite familiar with rust and rust stains in the washroom and this definetly isn’t it.
Inside my toilet bowl and on the floor/tile of our tub red stuff forms after a short while (3-4 days) after cleaning. It cleans quite easily and I don’t need any wicked chemicals or hard scrupping to remove it. It is kind of a “bright” red, lighter than rust in color… almost has a pinkish hue.
Any idea what it is? Is there some kind of bacteria or something that is comonly this color found in washrooms/showers?
Just to remind you: IT IS DEFINETLY NOT RUST.
If it matters, I’ve only seen this in our new home (brand new, just built). The pipes are all plastic, save a very short stretch of pipe off the hotwater tank that is copper. The water in our city is chlorinated and flouride is added. It has quite a low iron content though, IIRC.
I get the same crap in my bathroom. I’ve found it happens especially in the areas of the tub where water my sit for a while and also on my calk around the faucets. I concur with An Arky that it is most likely an algae. The onlly thing (so far) that I’ve found that kills it is any bathroom cleaner as long as it is accompanied by feverish scrubbing. Bleach will get rid of it almost instantly, but I’ve found, finally, the thing that will prevent it and that’s Clean Shower or products like it. Sorry couldn’t be of more help.
I get the same stuff around plugholes and where the water trickles at the end of flushing the toilet. You can see traces wherever water pools for long. It isn’t a living thing because it doesn’t spread, it’s just a stain. It’s something local because when I lived a few miles up the mountains it didn’t happen. The club nearby has the same stains in the washbasins in the toilet. I find that lemon juice gets it off best.
I doubt that it is the cause of bernse’s problems, but Serratia is a bacteria that can make the things it grows on turn red. As the link above(briefly) points out, this is a likely cause for some of the “miracles” where “blood” appears on bread, etc.