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What is Hard Water?

USUALLY EXPRESSED IN GRAINS PER GALLON

Hard water (or water hardness) is a common quality of water which contains dissolved compounds of calcium and magnesium and, sometimes, other divalent and trivalent metallic elements.

Hardness prevents soap from lathering, and typically causes the buildup of hardness scale (such as seen in cooking pans).

Dissolved calcium and magnesium salts are primarily responsible for most scaling in pipes and water heaters and cause numerous problems in laundry, kitchen, and bath.

Hardness is usually expressed in grains per gallon (or ppm) as calcium carbonate equivalent.

Symptoms of Hard Water include:

  • Stiff, dingy laundry
  • Mineral deposits on dishes and glassware
  • High soap usage & need for fabric softeners
  • Extra work to remove soap curd on bathtubs & shower stalls
  • High energy costs, possibly due to scale build-up in pipes and on appliances
  • Scale build up in sinks, tubs, faucets & appliances

What is Soft Water?

Soft water is defined by American National Standards NSF/ANSI 44 and NSF/ANSI 330 as water containing <1 grain of hardness per gallon (or <17.1 mg/L hardness).

Water treatment can improve hardness issues

Scale deposits from hardness buildup affects fixtures and appliances found throughout the entire home or business. For this reason, hardness is typically addressed with treatment of water for the whole house or building rather than just at a specific faucet.

Hardness minerals can be reduced in water for the whole house to make it “softer” by using one of the following means:

Chemical softening—lime softening, hot and cold; lime-soda softening

Membrane separation softening—Nano filtration

Cation exchange softening—inorganic, carbonaceous, or organic base exchangers