Packaged drinking water is not to be confused with genuine mineral water. Water drawn from an underground source or a spring and containing dissolved solids is termed mineral water. The minerals present in the water impart a distinctive taste to the water. Sometimes minerals such as calcium and magnesium are added to bottled water, but that is not the same as natural mineral water.

• Water purification systems for the home must be chosen with care

In addition to the methods mentioned above for water purification at home, there are two fairly common and effective methods: the charcoal filter cum ultraviolet light treatment systems and the reverse osmosis (RO) systems.

These systems must be chosen when tap water is not good enough.

Any ultraviolet light cum charcoal filter system must be chosen with care by ensuring that it confirms to some reasonable standards of quality. In general, such systems do not eliminate many chemicals and some micro-organisms.

An effective RO system can eliminate most impurities but the danger here is that it will also deprive the water of many essential nutrients. However, when tap water has dangerous chemicals or microbes present, then an RO system can be very useful. Once again, any such system must confirm to accepted standards. Water softeners are being sold aggressively today but are not recommended for drinking water.

There are many home water purifier/systems available in the market.

Here’s what they claim to do. And what they cannot:

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