Bro Jack wrote:

...Plumber said, though, that well water also contains calcium which
after many years collects at the bottom of toilet drain, narrowing it
and risking backflow. Sort of like an artery that closes up with
fat/cholesterol as we age.

Is this true? Thanx, Marie

We autopsied one toilet (with a sledge hammer :-) that only lasted
11 years from the time it was new until it stopped working when
the narrowest part of the throat became the size of a hot dog.

Nick