"Hard water" is that which contains mainly magnesium and calcium ions. It is of big disadvantage because it does not lather easily and it forms scud in boilers and pots. Water can be softened by passing it through a mineral tank that contains beads, where the calcium and magnesium ions are replaced by the more soluble potassium and sodium ions. This effectively renders the water "soft". You use less soap with soft water and lime scaling isn't as pronounced. Also, your skin feels smoother after you bath with softened water.
Water filter cartridges are the main components of your water purifying system. The cartridges perform a variety of functions. First, they remove any sediment present in your incoming water supply. Also, they eliminate bad taste from water, through the use of charcoal or granulated carbon filters. Lastly, cartridges remove any micro-organisms present in your water.
Reverse osmosis involves the passage of impure water through a semi-permeable filter membrane. Originally, the water and its impurities would move from a region of lower concentration of the water molecules to a region of higher concentration of the water molecules, through a semi-permeable membrane. When a higher pressure filter press is applied on the side with higher concentration, the water molecules pass through the membrane, leaving the impurities on the other side. Thus you get clean safe drinking water.
Water filter cartridges may be considered the "engines" to your water purifier. Cartridges have 3 functions. They eliminate sediments that may have