How to buy Water Purifier Guide

Permionics UF membrane water purifiers review

Permionics makes membrane water purifiers with ultrafiltration UF, Nanofiltration NF and Reverse Osmosis RO membranes. Permionics has been, so far, the only manufacturer of membranes in India. This is the link to the official website of Permionics water purifier. The advantages of membrane water purification is now an accepted fact universally. Membranes do not try to kill the germs in water by using chemicals or UV rays, but instead removes the bacteria and viruses in water. Bacteria and viruses cannot go through the membrane holes or pores, because the bacteria and viruses are much larger than the holes or pores in the membranes.

So water that has passed through a membrane water purifier is completely free of all bacteria, viruses, parasites and their eggs. Membrane water purification is the best method of water purification since it physically removes all the germs dead or alive, from the water. This is not the case with water purifiers using UV or Germ kill chemicals. Hopefully the germs will die with the UV or chemicals, but their bodies remain in the purified water. If those bacteria, viruses or their eggs are not fully dead, then they will come back alive, in your stomach may be.

As we have explained in our page on Membrane water purification, there are three main types of membranes used in water purification - ultrafiltration UF, Nanofiltration NF and Reverse Osmosis RO membranes. UF has the biggest holes or pores of the three membranes. UF holes or pores are much smaller than the smallest of viruses and it will block the passage of all bacteria, viruses, parasites and their eggs. NF has smaller pores than UF so it not only blocks all bacteria, viruses, parasites and their eggs, but also blocks passage of larger molecules like those of Arsenic, Calcium, Magnesium, Heavy Metals, etc. but will allow smaller monovalent salts like those of Sodium Chloride to pass through. NF is the ideal water purifier where the water TDS is not too high, not more than 600 ppm TDS, because it needs much less pressure than an RO water purifier and also the waste water is much less. RO is suitable to purify waters with higher TDS and gets rid of all impurities in drinking water. Permionics have the full range of all three membrane water purifiers. Permionics rightly has chosen to stay away from the marketing gimmicks of adding UV to membrane water purifiers. UV is no match for membranes when purifying water. Buying a water purifier with a UV after membrane purification is just waste of money.

Permionics Pureflo UF water purifier Models

Permionics Pureflo UF water purifiers comes in three models as show in the picture below. The models in the picture are the Pureflo UF – ECO on the left, Pureflo UF in the middle and Pureflo UF – 80 on the right.

permionics UF water purifiers with ultrafiltration membranes
Permionics UF water purifiers with ultra-filtration membranes

One of the biggest advantage of UF water purifiers is that UF water purifiers can purify water without the need of electricity. The features and specs of each of the above three models of pureflo UF water purifiers are given below

Pureflo UF – ECO

Ther pureflo UF - ECO is an online UF water purifier without a purified water tank. This is a very economical water purifier and the cheapest water purifier in the Permionics Pureflo water purifier range.

Pureflo UF

The Pureflo UF is a storage type UF membrane water purifier with the following features and specifications

Pureflo UF – 80

Permionics Pureflo UF Water Purifier Advantages

Permionics NF and RO water purifiers

The image below shows on the left the Pureflo NF (nano filtration) and on the right the Pureflo RO water purifier. Their features and specifications are as follows:

Permionics Pureflo NF and RO water prifiers
Permionics Pureflo NF and RO water prifiers

Permionics Pureflo NF water purifier

Permionics Pureflo RO water purifier

Suitable for waters with more than 600 ppm and less than 2000ppm TDS. Features and Specifications are as follows:

Buy Permionics water purifiers online

Clik on this link to see all models of Permionics water purifiers and their price

Membrane Water Purifiers are the best Water Purifiers

Membrane based water purifiers are the best Water Purifiers because they filter out all bacteria, viruses, parasites and their eggs. This is because membranes are such fine filters with pore size (filtering hole size) less than 0.01 micron. A micron is one millionth of a meter (0.000001 meter or 1/1000 of a milli-meter). The size of the smallest virus, the very smallest of germs, is more than 0.02micron in size and they are blocked by membranes whose pore size is less than 0.01 micron.

Other water purifiers try to kill the germs in water by using Chlorine Chemicals or by using only Ultraviolet light. They do not publish the micron rating of their filters - but it is believed to be in the range of 5 microns. Thus they can give clear looking water by filtering out the larger dirt particles in the water, but are unable to filter out viruses, germs and their eggs. So they depend on their germ killing mechanisms to purify drinking water. The supposedly dead germs and their eggs are not removed and remain in your drinking water.

The germ killing ability of these water purifiers have been in question for some time. For example, cysts of Giardia and Cryptosporidium are not killed by chlorine. Click here for details. There are several other instances where Government research institutions have tested the germ killing efficiency of water purifiers and found most of them could not be sure of killing all the germs in drinking water. It has also been reported that purifiers which try to kill germs with chemicals, do so by using chemicals which are harmful for human consumption. Here are the links to these reports.

Membrane Purifier passes Govt. of India Institute's Virus test

The 'Times of India' newspaper report dated 17 Sep. 2010 says that a Government of India Institute tested 8 leading Indian brands of water purifiers and found only 2 that worked to remove Hepatitis Virus. Of the 2 that passed, a Membrane Based Water Purifier is mentioned first as having passed all the tests........Link to full report in 'Times of India'

Ultra Violet or UV Water Purifier Problems

UV light inside these purifiers gets blocked when scale forms on the UV bulb, due to heat from the bulb. The scaling problem is intensified when UV unit is 'on' and there is no flow of water through it. If the UV bulb is kept 'off ' then chances of bio-growth like algae or slime, forming on the glass around UV bulb exists, and this could block the UV rays. Therefore either 'on' or 'off ', UV can become ineffective after some time.

Nature uses Membranes

The coconut tree uses membranes in its roots to purify dirty ground water surrounding its roots, and sends up the purified water to fill its tender coconuts. Membranes are such good water purifiers, that tender coconut water can be injected directly into people as an Intravenous Transfusion fluid in emergencies. (The intravenous use of coconut water: The American Journal of Emergency Medicine). During World War 2, many wounded American soldiers were saved in the Pacific War Zone battlefields, using raw tender coconut water as the drip plasma, the Intravenous Transfusion fluid.

About Permionics Company

The Permionics membrane base water purifiers have been in the market for about 30 years, but they were never aggressively advertised. Permionics has the distinction of being the first and only manufacturer of membranes in India (since early 1980s). It should be noted that an Indian Scientist, Dr. Srinivasa Sourirajan, while doing research at UCLA (University of California, Los Angeles) co-invented Water Purification Membranes in the early 1960s. Dr. Sourirajan visited the Permionics factory in its early days.

Permionics has successfully used membrane technology in several applications such as milk concentration, whey fractionation, waste water recycling of dye industry, etc. Permionics pioneered the use of Membrane technology in the Pharmaceutical industry by installing Asia's first membrane based system for concentration and purification of Streptomycin in 1981.

Best way to buy Water Purifiers in India

The best way to buy Water Purifiers in India is to first look at all models of Water Purifiers available online at the leading online Retailers in India. For example on the online webpage of All Water Purifiers available in India on, you will find the full range of Indian Water Purifiers complete with their best discounted price and full specifications. This is great information, and you can decide on which model of water purifier to buy. With the model of water purifier you want to buy finalised, you can go to local shops to try and find the model of water purifier you have chosen and see if you can get at similar price of that at In most cases the price from Amazon will be cheaper, because they buy in bulk from the manufacturers direct and they sell huge volumes because they are the world's largest and most trusted online retailer. If you buy from Amazon, they will arrange to have the water purifier installed in your house, usually free of charge.

Warranty and other facilities offered through Amazon are usually better than what you can get from local agents of water purifiers.

All pages in our website

Below are links to all the pages on this website and we hope you will make full use of all the great information about Indian Water Purifiers provided here.