In alt.home.repair, on Sat, 08 Aug 2015 11:08:47 -0400,
wrote:

On Fri, 07 Aug 2015 18:55:14 -0400, micky
wrote:

Because there has been no detectable crud in the water that comes out of
the sink that I touch with my hands, and if there were crud in the bath
water, I think I'd notice it.

The stuff that accumulates in the water heater is dissolved calcium in
the water. YMMV depending on what is in the water to start with. When
I was in the north east our water was very good and water heaters
lasted forever. Here in Florida, they don't last that long. Ten years
is typical.

Bear that in mind, Taxed.