My answer to Which water purifier works best in a city water?
Answer by BlueLife India:
Important to note:
City water, Do we have a standard specification for any City Water? And what does it consists of when you go with analysis report?
Any city water authority is able to provide drinking water basis on best available source in the city, and then treat and distribute through pipelines. Chlorination is the treatment process in most of the cities.
Is Chlorinated water safe to drink?
Consider some well-known attributes of chlorine.
Let's say, "the dark side" of the saviour. A PhD chemist friend put it this way: "If I were assigned to go into a lab and produce a menu of known carcinogens (cancer-causing agents), the first thing I would do would be to grab-up a cylinder of chlorine and start bubbling it through some water that contains naturally occurring organic acids (humic and fumic acids – as are found in all natural bodies of water like rivers, lakes, reservoirs, etc.)."
"Any municipal water supply can be made as pure as mountain spring water. Chlorination destroys all animal and microbial life, leaving no trace of itself afterwards". This statement reflected opinion accepted until recent years when halogenated organic compounds, such as chloroform, were identified in chlorinated drinking water supplies. Recent surveys show that these compounds are common in water supplies
These concerns about cancer risks associated with chemical contamination from chlorination by-products have resulted in numerous epidemiological studies. These studies generally support the notion that by-products of chlorination are associated with increased cancer risks.
Hence, Chlorine removal process is one important stage in water purification/water purifier.
What does impure water contain?
1. Physical Impurities/ Sedimentation
Can be removed by a sediment filter cartridge made of ceramic/ polypropylene etc.
2. Bad Color and Odor/ Smell
Can be eliminated by an activated carbon filter cartridge
3. Biological contamination viz., Bacteria & Virus
a. Can be eliminated through Reverse Osmosis (RO) Process
b. Can be deactivated by Ultra Violet (UV) Sterilization process
4. TDS (Total Dissolved Solids)
Can be removed excess salts through Reverse Osmosis Process, by retaining 2 to 5% and up to 10% of TDS/ available minerals in feed water, based on quality of RO Element used.
Available Water Purifier Categories for Residential Application:
a) RO, RO+UV water Purifiers (Bit expensive than other two)
b) UV Based Purifiers (Medium Price Range)
c) Gravity based purifiers (Low Price Range)
a. Source water ranging from 200 ppm to 2000 ppm TDS will be good to treat through Reverse Osmosis process comes with a purified water storage tank, and the product water will be good in taste, and above mentioned impurities 1, 2 3 and 4 will be removed/ eliminated, the taste may be good to consume with purified water, an available comprehensive purification process.
b. UV Based Purifiers are also be used for less than 200 ppm TDS source water, but
i. Biological contamination i.e., virus and bacteria will be deactivated in UV disinfection process
ii. Treated water is not suggested for long time storage before consumption, storage tank is not suggested for drinking water purpose.
iii. There will not be much taste and TDS difference, from source water to purified water
c. Gravity purifiers are available mostly based on Chemical based like Chlorine or Iodine or ceramic filter based, or UF based. These gravity models are comes with a very limited life of consumables, Refills/consumables are required frequent change.
Hence, for any source water the effective process of purification is Reverse Osmosis (RO), RO+UV and Second UV Based, last Gravity Purifier.
Please visit us for BlueLife Range of Water Purifiers at
For more details contact us at:
BlueLife TechnoSciences India Private Limited
1-10-63&64, Chikoti Gardens, Begumpet, Hyderabad – 500016, India
Toll Free: 18005991234 (India)
WhatsApp: +91 9100044319
Landlines: +91 40 27765099, 27766099; Fax: +91 40 27768099