Pink residue is generally not a problem with water quality.
pink residue is likely a result of airborne bacteria,
which produce a pinkish or dark gray film on regularly moist surfaces.
Such surfaces include toilet bowls,
Some people have also noted that the pink residue appears in their pet`s water bowl,
which causes no apparent harm to the pet and is easily cleaned off.
Many experts agree that the bacteria that causes these pink stains is most likely Serratia marcesens,
a bacteria which is found naturally in soil,
and in animals.
which produce a characteristic red pigment,
thrive on moisture,
and phosphates and need almost nothing to survive.
The pinkish film often appears during or after construction or remodeling,
when dust and dirt containing Serratia bacteria are stirred up.
Once the bacteria is airborne,
it will seek a moist location in which it can grow.
Some people have reported that the pink residue only appears during certain times of the year,
when their windows are left open for most of the day.
This bacteria is present in a number of environments and wind can carry the airborne bacteria or stir up dust in which the bacteria is present.
The use of activated carbon filters,
which remove chlorine from the water,
can make the problem worse.
The absence of the normal levels of chlorine in tap water allows Serratia to thrive.