You didnÂt mention if youÂre on municipal or well water

Thinking back to my college days and chemistry, I recall that chlorine will react with potassium and sodium nitrate and produce a brownish red color. Somewhat like iodine.

Are you softening your water? Possibly with potassium chloride?

Good point. I'm just on town water so I'm not doing anything extra to it but maybe I'll get one for my other toilet just to see if it does it there too...

Those blue things are bad for the plastic parts in the tank (and supposedly void warrantees). Maybe it's already degrading the flapper or something - just a wild guess.

The added chlorine does eat the rubber flappers.

Just as point of interest, I use the units from Kaboom (sp) that are a cartridge and hang inside toilet. They are installed on the fill tube in the middle and dispense/metered every flush directly into the bowl, via the overflow of the flushometer, thereby never having any contact with items in tank. More money, bt a lot less waste and no staining on a infrequently used toilet.

I think it's the chloride been using it just a couple of days had same issue red water looked it up came here checked tack and.... red rubber flapers look weird

I have two toilets in my house, one flushes blue, the other pink… i lifted the back of the toilet lid to see if it had disolved too quickly, and found a perfect divide of half pink, half blue water. i should have taken a picture because the blue has finally settled, but for about a month it only flushed pink water. sci is crazy.