Mineral water was in fashion a decade ago, today De-mineralized RO water is in fashion. I can understand the need of people who live near the sea, asking for desalinated water for drinking, but why the rest of the country is going for bottled water cans and RO Purifier.

Domestic RO machines are expensive units costing 5-10k each and every 6-8 months the membrane needs to be replaced which costs almost ½ the unit cost itself. Even after ignoring the cost of piped water & electricity, the personal RO water cost almost the same as the commercial bottled water. Also to generate 1 glass of RO water, the filter wastes away another 3 glasses of piped water through the thin white pipe from the purifier to the drain. In a country, where ground water levels are depleting and portable water not available to 80% of the households, this seems like an expensive luxury.

There are some regions which have dissolved heavy metals, nitrates and other dissolved contaminants for which RO is the only treatment mechanism. However just using a blanket RO filtration everywhere may be foolhardy. A simple 100-300/- water purity test can prove to you that the RO marketing campaign is nothing more than a gimmick to make you spend more.