What does bicarbonates in water mean in practice?
They form a buffer with carbon dioxide and carbonate, stabilise pH and contribute to scale formation when water is heated.
When does it matter?
Bicarbonate concentration is not the same as hardness, although together with calcium and magnesium it defines carbonate hardness.
Which solutions are related to it?
Assess it with pH, alkalinity, calcium and CO2; reduction may use dealkalisation, RO or controlled acid dosing.