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Water Treatment Issues:

Acid Water

Algae, cyanotoxins

Alkalinity

Alum (Aluminum Sulfate)

Aluminum

Ammonia

Arsenic

Asbestos

Bacteria

Barium

Benzene

Bicarbonate Alkalinity

Boron (Borate, Boric Acid)

Brackish Water

Bromine

Bromate

Cadmium

Calcium

Carbon Dioxide

Carbon Tetrachloride

Chloramines

Chloride

Chlorine

Chromium

Color

Copper

Corrosion

Cryptosporidium

Cyanide

Dichloroethylene

Endocrine Disruptors

Fluoride

Giardia Lambia

Hardness

Heterotrophic Bacteria (HPC)

Hydrogen Sulfide

Iodine

Iron

Iron Bacteria

Lead

Magnesium

Manganese

Mercury

Methane

MTBE

Napthalene

Nickel

Nitrates and Nitrites

NMDA (N-Nitrosodimethylanime)

Norovirus

Odor

Organics

Perchloroethylene (PCE)

Perchlorate

Pesticides

pH

Pharmaceuticals

Radon

Radium

Selenium

Silica

Silver

Strontium

Sulfate

TDS (Total Dissolved Solids)

Trichlorethylene (TCE)

Tritium

Uranium

Vanadium

Vinyl Chloride

VOC


Calcium


Calcium, the most abundant cation in water, is the main component of hardness, as calcium carbonate.

Calcium comes from rocks, especially gypsum and limestone. In most water, calcium ions are the predominant cations.

Calcium must be removed from water used in many industrial processes, and an entire industry is based around removing hardness from residential water. As hardness, calcium can cause severe damage to residential plumbing pipes and fixtures.

Calcium is more a plumbing issue than a health issue, though some schools of thought have it that lack of calcium as in distilled or reverse osmosis treated water is not healthful. There is no convincing evidence to support this view, or for that matter the opposing view that water with calcium is harmful to health.

Calcium Removal - Calcium is readily removed from water by a simple sodium form ion exchanger, commonly known as a water softener.  Reverse osmosis removes 95% to 98%, but removal of hardness usually causes scaling of RO membranes. Calcium can also be removed by deionizers (hydrogen form cation exchangers), dialysis, distillation and ultrafiltration.