=Calcium Scale=
...is usually uniform and covers both plaster and pebbles in a pool. Calcium scale usually feels rough, like sandpaper, on the pool surfaces.
...the pH. When it exits through the grout, it evaporates and leaves all that scale behind.
...absorb water.<ref>https://www.troublefreepool.com/threads/crazy-amount-of-scale-showed-up-after-elsa.237440/post-2078434</ref>
...usty” rebar that is coated in mill-scale and is not genuinely rusted. Mill-scale has even been shown to improve the adhesion between rebar and concrete.<ref
=Waterline Tile=
