Well, whatever the reason...I'm sure it's harmless.
"Serratia will not survive in chlorinated drinking water. However, where water stands long enough for the residual chlorine disinfectant to dissipate, such as a toilet in a guest bathroom, or on a shower curtain, the pink color may develop. Once established, Serratia is difficult to eliminate entirely. However, regular and thorough cleaning, followed by disinfection with chlorine bleach, is the best means to control the organism."
"More people indicate the problem occurs in the summer months when temperatures and humidity are higher, and especially if windows are kept
open for any length of time."www.hkywater.org/i-didnt-know-that/pink-stains-in-your-toilet-bowl
PeteZa, have you found it worse in the summer months?
Moderator, Lyme Forum
Symp started April/2013; Buhner's Lyme May 15-July24/14; Igenex pos. July 3/14
Doxy: July 4-Aug.24/14;Zithro July26-Aug24/14; Amox + Proben. Aug. 29/14;
added biaxin Sept. 26/14
Disc. amox,added Ceftin Nov. 20th.;
Disc. biaxin added Buhner bart herbs Dec/14;Jan/15 pulsing Tinda (w/ Ceftin);
Abx/herb break Apr-July/15; July-mino; Aug. added Rif;
Nov./15 mino - to biaxi