Water Hardness (and Water Softeners)
What is Water Hardness?
Hardness in drinking water is caused by calcium and magnesium - two nontoxic, naturally occuring minerals in water. Excessive hardness makes it difficult for soap to lather, leaves spots on dishware, reduces water flow and can cause pipe, valve and drain scaling.
Does hard water really create problems for the homeowner?
Hard water can be a very costly addition to your home primarily because it leaves a residue called hard water scale on all washable surfaces.
Over a period of time, hard water scale can clog your plumbing which eventually reduces water pressure. It damages water heaters, dishwashers, washing machines, coffee makers and virtually all appliances through which water passes. This scale leaves spots or streaks on dishes and glassware, and dulls the look of clothing, floors, sinks, tubs, and even hair.
Corrosion often occurs because of highly acidic water that gradually eats away pipes, appliances, heaters, boilers and air-conditioning units.
High TDS may indicate hard water, which causes scale buildup in pipes and valves, inhibiting performance. Since TDS is related to water hardness, using a TDS meter can be your first step in determining the degree of hardness of the water. Generally speaking, the higher the level of TDS (ppm), the higher the degree of hardness.
Water hardness is typically reported in grains per gallon, milligrams per liter (mg/l) or parts per million (ppm). One grain of hardness equals approximately 17.1 ppm (mg/L) in TDS.
Note that since TDS includes hard solids and soft solids, 17 ppm does not necessarily equal 1 grain of hardness.
How is water hardness treated?
If you have a hard water problem, your solution could be through a water filtration system such as Reverse Osmosis (RO) (which will remove most minerals), Distillation (which will remove all minerals) or a Water Softener. For a whole house, reverse osmosis or other types of filtration are typically more costly options than a water softener.
Do water softeners remove TDS?
Water softeners do not remove TDS. Instead, water softeners work through a process of ion exchange. As water flow through the water softener, it will pass through a resin, bed of small plastic beads or chemical matrix (called Zeolite) that will exchange the calcium and magnesium ions with sodium ions (salt). Therefore, the TDS level will remain virtually constant (there may be minor differences).
Water softeners are designed to "soften" water so that it washes brighter, rinses cleaner and feels much better.
Since a water softener does not lower the TDS level of your water, an additional filter may be necessary for your drinking water. The need for an additional filtration system is entirely dependent upon your source water. Always test your water to determine your needs prior to investing in a filtration or purification system.
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