Definitioner
Soft Water
any water which contains less than 1.0 gpg(17.1 mg/l) of hardness minerals, expressed as calcium carbonate.
Hardness
a characteristic of natural water due to the presence of dissolved calcium and magnesium; water hardness is responsible for most scale formation in pipes and water heaters, and forms insoluble" curd" when it reacts with soaps. Hardness is usually expressed in grains per gallon, parts per million, or milligrams per liter, all as calcium carbonate equivalent.
Capacity
an expression of the quantity of an undesirable material which can be removed by a water conditioner between servicing of the media, i.e., cleaning regeneration or replacement, as determined under standard test conditions. For ion exchange water softeners, the capacity is expressed in grains of hardness removal between successive regenerations and is related to the pound of salt used in regeneration. For filters, the capacity may be expressed in the length of time or total gallons delivered between servicing.