The Best RO Water Purifiers in India 2021 – Buyer’s Guide & Reviews

By Arindam Roy

Finding the best water purifier for your home is a challenge in India today. Should I go with UV/UF technology or RO one?

Why should I even get a water purifier?

According to a study in 2000, nine districts in West Bengal have arsenic levels in drinking water above the WHO limit. This increased the usage of water purifiers, which form a share of 3% of the consumer electronics market today.

To lower the excessive solute content in our water, only RO water purifiers can meet our needs today.

In this article, you’ll get to know the answers of :

  • Why do you need a water purifier?
  • How many types of water purifiers are there?
  • Which top purifiers are of leading brands?
  • How to select a water purifier that is best for your home?
  • How does water purifier work?
  • When do water purifiers need servicing?

Here’s a list of top ten water purifiers in India today:

1. KENT New Grand 8 Liters Wall mountable RO + UV+ UF + TDS :Best Water Purifier

Best RO Water Purifiers in India

This water purifier by Kent is best for bacteria-laden water, municipal water, or water supply with high pesticides or herbicides in it. Its use is optimal for Indian homes and offices, and its wall-mountable feature makes it easy to use in a small space.

Reverse Osmosis system uses external pressure to move water from concentrated to diluted side through a semi-permeable membrane. While UV waves inactivate any bacteria and viruses.

This purifier of 40 x 23 x 54 cm and 9.4kg has a storage tank of 8 litres and consumes 60W power. it uses both UV and UF purification systems, along with RO purification.

So, it’s a dual purification method.

Check your water TDS before buying it. It can be used for TDS 500-2500, and you can also control the TDS of the output water. It’s recommended to not keep your TDS less than 50mg/L. As it removes all the good minerals along with the impurities at that low setting.

In its core, there is a RO membrane kept within membrane housing to avoid any damage. Its capillaries are of 0.0001 microns, and it has a capacity of purifying 20L water/hr.

Its material is ABS food degradable plastic to avoid corrosion. SMPS is vertically mounted to prevent water exposure. It has a push-fit to avert any leakage.

Keep your Kent purifier within 3 meters of your water source. Don’t keep it in a cabinet.

Keep your inlet water between 10-40°C. Turn it off if you are not going to use it for more than 2 days. Keep the outlet water pipe at a lower level to prevent backflow.

You know how amazing and top-notch this purifier is?

It has:

  • Auto flushing systemof RO membrane to prevent fouling and scaling. It improves the TDS rejection rate as well.
  • Alarms
    • UV fail alarm when UV lamp malfunctions
    • Filter change alarm after 700 hours use since last filter change
  • Computer-controlled syste
    • UV stabilization delay of 2 seconds
    • Purification delay of 5 seconds
  • Automatic
    • It turns off when storage tanks are full, and restarts when the level lowers
    • It switches off when the pressure of inlet water is less than 0.3kg/cm2.
    • If you have no electricity then no water is rejected

I know after reading all this, you are wondering why you haven’t bought this already?

I know I am!

So just to balance all the perfection, let us tell you some of its weak points as well. Although I must say, they were really hard to find.

Before you buy it, you have to understand that it rejects 65% of the water that goes into it. That means 650ml out of 1 litre of water. Instead of wasting that much water, we recommend you to use it for other domestic purposes, as it is free of dirt and completely usable.

Its maintenance is a bit expensive. You need to change the filters, UV lamp, and RO membrane once a year. Drain the tank once in 15 days.

  • Dual purification
  • Internal TDS controller
  • Auto flushing system
  • Automatic
  • Large water rejection
  • Expensive maintenance
  • Taste of the water may change after

2. Eureka Forbes Aqua-sure from Aqua-guard Smart Plus RO+UV+MTDS: Top Quality Water Purifier

Best RO Water Purifiers in India

If you live in an area with a high TDS water supply from tank, borewell, or tap, then you ought to consider this top rated water purifier. Water with high TDS, containing heavy metals, and high contamination level, needs both these above technologies.

6L water capacity tank comes with it. it uses 230W power to function. If you are using geyser for hot water, do not connect your hot water supply to this purifier. It uses 10-40°C water only.

It is made of good quality food grade plastic, purifying water for TDS 200-2000. Check the TDS of your water supply before buying this purifier.

Are you worrying whether it will fit in your kitchen? It is compact with a size of 318 cm (Length) X 205 cm (Width) X 460 cm, and weighing 5.6kg.It takes 15-20 minutes to produce 6 liters of water.

It has a smart energy-saving mode that shuts off your water supply if the storage tank fills up. LED lights and indicators make it user friendly. They display when it is working, or when water pressure is low, or no incoming supply is there, or any error occurs or if the tank is full.

You can mount it on a wall or place it on a countertop. The purifier works fine during voltage fluctuations. Eureka offers a 1-year warranty on the product.

Do you know how comprehensive the purification process is? It has 6 steps:

Clarity cartridge: it is a sediment filter to remove dust, dirt, sand, and rust, etc.

Chemi-block: this removes chlorine, getting rid of its smell and taste. Pesticides, organic impurities, and particles that increase turbidity are removed.

Membrane life enhancer: this prevents RO membrane scaling, to enhance its life.

RO cartridge filtration: this removes hardness, decrease TDS. Heavy metal, pesticides, bacteria, viruses, protozoa, and cysts are removed.

The taste enhances cartridge filtration: here carbon granules polish the water to enhance its taste. It removes organic impurities.

UV disinfection chamber: inactivates disease-causing microorganisms.

This purifier reduces TDS by up to 90%. Use it for water pressure of 4.2 – 42.6 psi. if your inlet water pressure is lower, then use an external booster pump. If the pressure is higher, then use pressure reducing valve.

It is important to properly maintain your purifier. Flush out the first filtration water. Drain storage tank if not used for 2 days. All filters except UV lamp need replacement after 6000 litres of water is filtered through them. That is 1000 fillings of the storage tank.

Do backflush of clarity cartridge every 1-2 months. Disinfect storage tank every 2 weeks.

Like all RO purifiers, it wastes a lot of water. Out of 1 litre, 650ml is brine. Use this water for washing clothes or cleaning floors etc.

  • Smart design with LED indicators
  • Protection from voltage fluctuation
  • Excellent filtration for high TDS, highly contaminated water
  • Smart energy save mode
  • TDS regulator
  • A lot of water is wasted
  • 6L storage capacity is for small families only
  • Outlet water drainage is very slow

Also read: Best Water Purifiers under ₹10000

3. Kent Pearl 8-Litre Mineral RO+UV+UF: Excellent Water Purifier

Best RO Water Purifiers in India

Kent Pearl 8-Litre Mineral RO+UV+UF Water Purifier is one of the most effective Ro water purifiers according to our skilled and experienced experts. It comes with the design of double purification by RO, UV, and UF. Even this particular water purifier is systemized with TDS controller.

The controlling system of this purifier goes through the system controlled by the computer. Apart from that, it comes with a systemization of filter change alarm and UV fail alarm. It has a water tank with a capacity of 8 liters.

It provides you the benefit of leak-proof performance with the help of push-fit components. It gives you comfort in regards to connecting with all kinds of water sources like bore-wells, overhead storage tanks, water tankers, and even municipal taps.

Why is it special?

Do you like to buy a RO water purifier with double filtration? If yes, then positively you should buy the above-mentioned water purifier. It is good to know that this purifier is systemized with RO, UV, and UF. Moreover, the purifier comes with a facility of the TDS controller.

It is completely computerized. It will make you alert through two alarming systems such as change alarm for filtration and UV fail. The machine will save your time as you no need to switch on it two or three times. t is completely computerized. It will make you alert through two alarming systems such as change alarm for filtration and UV fail.

The machine will save your time as you no need to switch on it two or three times a day. The reason behind that is the water tank capacity of this purifier is 8 litres.

Even the purifier will make you benefited providing the system of leak-proof performance. In that case, it comes with a system of push-fit components.

You will have multiple facilities regarding the connection of it with any source of water. For that particular case, you can take overhead storage tanks,bore-wells, water tankers, and even municipal taps.

  • Systemized with double purification
  • Facilitated with TDS controller
  • Fully Computerized
  • 8 liters water capacity
  • Push-fit components enabled
  • Suitable for all types of water sources
  • Something hassle in maintenance

Read more: Best Water Purifiers under 5000

4. HUL Pureit Copper+ Mineral RO + UV + MF 8 liters: Highly Rated Water Purifier

Best RO Water Purifiers in India

If you have a water supply with high TDS above 300ppm, then give this purifier a try. It reduces 90% TDS and reduces microbial contamination by UV disinfection.

RO needs a storage tank to use the water whenever you need it. It has a water capacity of 8 litres. It uses 60W power.

The water inlet temperature should be between 10-40 °C. The build material is sturdy with food-grade engineered plastic.

The purifier measures only 36.1cm X Width 35cm X Height 44.70cm, and weighs 9.5kg. it can purify 28 litres per hour.

To know how it works, here are the 7 steps purification:

Pre-sediment filter: this is made of polypropylene. It filters coarse and fine sediments like dirt, sand, etc.

Carbon filter: it removes chlorine from the water before it reaches the RO membrane. It also filters out pesticides and other organic compounds to remove bad smell and taste.

Mesh filter: it acts as a second filter to remove finer impurities.

RO membrane: this membrane hinders any salts, pesticides, toxic heavy metals, and microbes like bacteria, viruses, protozoa, and cysts. It makes hard water soft.

UV reactor: it removes bacteria, viruses, and pesticides.

Post RO Carbon filter: here carbon polishes water molecules. This improves taste.

Microfilter membrane: water is purified thrice to ensure the purest water.

The most interesting feature of this purifier is its copper charge technology. It charges water with 99.8% of copper. This helps in giving water antimicrobial and anti-inflammatory properties.

This copper charge is fresh for every filtration. The auto cleaning makes sure of this.

If you are not comfortable with drinking copper infused water, then it gives you the option of drinking RO water too. This dual dispensing system is user friendly.

Before buying this purifier, you should check its installation feasibility. The purifies water of pH 6.5-8.5 and with a pressure of 10-30 psi. make sure there is an electrical connection within 2 meters of the purifier. It comes with a 1.5m power cord.

The water inlet should be within 2 meters of water connection. Don’t use an extension cord. Purifier shouldn’t be installed above an electric socket.

The product comes with LED lights that give gentle reminders, like the need to change filters.

To increase the longevity of the product, you require continuous maintenance. Drain storage water if not used for 2 days. Replace water in storage at least once in 15 days. Disinfect storage tank at least once a month.

Like other RO filters, it wastes a ton of water. It wastes about 65% of water. Use this discarded water for washing and cleaning. It offers a 1-year warranty.

  • Copper charge technology
  • Dual water dispenser
  • Large storage capacity
  • You can use manual tap during
  • Needs electricity to provide copper charged water
  • No remineralization cartridge
  • High maintenance

Related post: Best Water Purifier For Home

5. LG Puricare WW150NP RO + UV: Outstanding Water Purifier

Best RO Water Purifiers in India

Among all the prominent water filter companies, undoubtedly LG is known as the most reliable one. As expected, this LG Puricare WW150NP RO + UV best Water Purifier also maintains that tradition and quality of the LG company. This advanced technology featured LG water purifier comes with an upgraded filtration method which eliminates all the mischievous viruses from water.

Let’s cast a brief look at the special features of it.

Which specifications have the ability to impress you:

Advanced RO filter function: The upgraded RO filtration process of this whole house water filter diverges all the bacteria from water while keeping all the minerals intact. Thanks to this 5 staged straining system for getting virus-free, clean water.

Tank construction: Whereas, a lot of water purifier comes with plastic made tanks, the LG Puricare WW150NP RO + UV Water Purifier offers a dual steel constructed tank. That means you can get surety of 100% purified drinking water. As the steel tank doesn’t permit any bacteria to grow in the water by maintaining it sanctified.

Water tankage capacity level: The Dual steel made tank comes with an 8L water tankage capacity by keeping it hygienic.

UV Rays: After every, the UV cycle gets started and stores in the tank after the completion of purifying.

Sterilization system: Thanks to the digital Sterilization function for not using any type of mischievous chemicals.

Easy to install: As it gets easily fitted in the walls, it doesn’t take much place to get installed and able to fit in the wall easily.

Mineral booster: This best LG RO purifier boosts the water with a lot of minerals.

Premium display setting: The extraordinary display system of this water filter, allows the users to see all the indicators even when the room is dark. With the help of this indicator, you can easily able to see the filter variation, the level of water.

  • Stiff stainless steel constructed tank.
  • Bacteria removing technology.
  • Mineral elaborating capacity.
  • Premium Display viewer.
  • 8L water storage capacity.
  • Little bit costly
  • Wasting a lot of water because of RO filtration

Relevant reading: Best Water Purifiers under ₹15000

6. Havells Max Alkaline 7-Liter RO+UV: Great Quality Water Purifier

Best RO Water Purifiers in India

If you are using water from a borewell or a tanker and it contains heavy metals, then this Havells purifier is just what you need. It lowers TDS of your water up to 90%. RO technology is deployed to achieve the required target.

UV disinfection kills or inactivates all the water-borne disease-causing bacteria, viruses, protozoa, and cysts. Furthermore, it is sufficient for an average Indian family with its seven liters storage embedded tank.

On the other hand, it generates alkaline water with pH ranging from 8-10. You don’t have the liberty of changing the pH level of the outcoming water supply. TDS is also fixed.

This purifier uses seven stages for purification. A pre-sediment filter, activated carbon block, RO technology, UV disinfection are some of the core stages.

Minerals technology is its best feature. If you’re tired of drinking the bitter-tasting purified water, then you should consider this Havells product. It makes the water alkaline, and that improves its taste drastically.

If you’re worried about losing all the essential minerals in your water along with the contaminants, then mineralz technology solves your worries. It adds all essential minerals and traces elements back into your water.

Revitalizer makes the water magnetic. This means that water molecules have more capacity to absorb these vital minerals.

The dimensions of the purifier are 27.3 x 38.2 x 49 cm, with a heft of 8kg. This compact design makes it suitable to fit anywhere. You can put it on a tabletop, or mount it on a wall.

It offers an iProtect purification monitor. It stops the water supply if the water is not fit for drinking.

This product is quite a user friendly. It has reminders for every malfunction. It is self-diagnostic and provides the user with alerts if the storage tank is full or when there is low incoming water pressure. It also alerts you when there is a UV lamp malfunction or the pump failure.

The flow rate of this purifier is up to 15 litres per hour. It consumes 45W of power. If you find the cleaning of the storage tank cumbersome, then its removable tank will benefit you. The tank also boasts a cover for protection again dust and insects.

Some of its drawbacks include excessive water wastage, no TDS meter, and no pH control of the outcoming water.

  • It provides alkaline water
  • Mineralz cartridge gives essential minerals
  • iProtect purification monitoring reduce water wastage
  • Smart alerts to make it user friendly
  • No pH meter is there
  • No TDS meter present
  • Water wastage
  • Bad aftersales service

You may also like: Best Graviity Based Water Purifiers

7. Ruby Economical RO + UV +TDS Controller Multi-Stage: Magnificent Water Purifier

Best RO Water Purifiers in India

If you have a family of four or more members and your water supply has high TDS with heavy metals then this Ruby purifier must be your priority.

It is most suitable to purify heavily contaminated water from borewell or tanker. It has a TDS controller so you can change the TDS of the outcoming water according to your needs.

The purifier has a large capacity.It stores 12 liters of water in its storage tank. It can generate nearly 12 liters of water on an hourly basis. Ruby recommends 75 liters of purification per day. You should not exceed this limit to ensure longer working life of the purifier. It provides you with the purest water using these six stages:

Pre-filter: this removes particles that exceed 5 microns, including dust, rust, and sand, etc.
Sediment filter: this provides additional filtration of particles exceeding 1 micron. Finer dust particles are removed at this stage.
Activated carbon filter: RO membrane is vulnerable to chlorine. So, this carbon filter removes chlorine with its taste and smell and other organic impurities, before reaching the RO membrane.
RO membrane: This softens hard water and removes many compounds including lead, fluoride, chromium, and barium, etc. This membrane also resists some organic contaminants including pesticides.
Post Carbon filter: This gets rids of objectionable taste and smell by polishing water molecules.
UV disinfection: It kills or inactivates bacteria and viruses.

This 9 kg purifier measures 27 x 45 x 57 cm. Its compact design enables its mounting on a wall. It can pump 100 gallons a day.

Before bringing this product to your home you should check the TDS and pressure of your water. It is suitable for TDS up to 1500 ppm and water pressure of 0.3 Kg/cm2 to 3 Kg/cm2. It has no alarms or LED indicators attached for reminders for any malfunction.

For auto on and off it features a float valve/ switch. When the storage tank reaches its maximum limit, it stops incoming water. As the water level decreases it moves down and automatically restarts the incoming flow of water.

It comes with a 1-year warranty on all its electrical parts excluding UV lamp. One thing more, the filters are not included in the warranty. You should change your RO filter once a year for the smooth functioning of this purifier.

  • TDS meter to change TDS of output water as you need
  • It is very easy to install
  • Low maintenance cost
  • The huge storage capacity of 15 liters
  • It tastes bitter
  • Water wastage is huge
  • Installation is unavailable at many places

Read more: Best Alkaline Water Purifiers

8. Kent Pride Plus 11067, 8 LRO+ UF+ TDS Cont.+ UV: Perfect Water Purifier

Best RO Water Purifiers in India

We all have the very eminent name in the genre of Ro Water Purifier in India which is the Kent RO Systems. It is a brand that is trusted by lakhs when it comes to the quality they provide to give you the safest drinking water. The Kent Pride Plus 11067, RO+UF+TDS +UV Water Purifier is among the top as it provides you with all the features that you always desired for your prominent Ro Water Purifier System to have.

Let’s look in detail about its features and specifications to give you an insight about the product:

Sleek Design: The sleek design of the system is one of the first attractive features. It is quite compact and will occupy less space in your kitchen or home.

The capacity of the tank installed: It comes with a great capacity of about 8L which provides enormous capacity to have water for the complete day and is hygienic too.

TDS Controller: One of the most significant features of this RO is the TDS Controller which makes it one of the finest RO Water Purifiers TDS controller helps u to retain essential nutrients and minerals in the water which is much needed by the body

UF Technology: Yet another important feature of the ROS is the UF which helps to remove harmful bacteria and cysts from the water.

UV in Tank: The last stage in purification of water is eliminating the dreadful bacteria and viruses which couldn’t be killed by UF technology. So UV in the tank in this RO helps to keep all the unwanted bacteria, viruses, and germs and provide safe and clean water.

  • Sleek and accurate design
  • TDS Controller to retain essential minerals
  • UV and UF technology to kill bacteria
  • Huge 8L water tank
  • A little heavy on pocket

Customer Service:

Our customers are very satisfied with our service, we install the RO on that very day of delivery and our customer care number is always available to resolve your issues. You can call at +919278912345 which is available from 9:00 am to 6:00 pm for all 7 days a week.

9. AO Smith Z8 Green RO 10 Liters: Best Performance Water Purifier

Best RO Water Purifiers in India

If your water supply has more than 300 ppm TDS and biological contamination is low, then AO Smith water purifier perfectly suits your needs. It makes use of reverse osmosis to lower the TDS up to 90 %.

This purifier uses normal temperature water that ranges from 5 to 45°C. Don’t try to connect hot water supply directly to this purifier. It consumes around 60 W of power. It is constructed from food-grade ABS plastic.

TDS of up to 2000 ppm is suitable for this purifier. You can’t change the TDS of output water.Because of its slow filtration, it comes with a storage tank. You can store approximately 10liters of water in it. It has an extensive purification system comprising of 8 stages:

  • Pre-filter: At this stage, it removeslarge dust, rust, and sand particles.
  • Sediment filter: another membrane filter to remove finer particles.
  • Carbon block: removal of chlorine and organic impurities takes place here.
  • Advance recovery technology: this feature is unique for a RO purifier. It recovers most of the discarded water.
  • Patented side stream RO membrane: It removes organic impurities, heavy metals,pesticides, and hardness of the water.
  • Mineralizer technology: It spares essential minerals in water that was filtered via the RO membrane.
  • ZX double protection dual filter:
    • SAPC (silver activated post carbon block): It enhances the taste of purified water.
    • SCMT (silver charged membrane technology): Silver benefits drinking water.

This purifier is efficient in saving the water, which is double the amount of water than other RO purifiers. Silver technology helps in making the water more beneficial for the human body.

If you live somewhere with a cold climate and yearn for hot or warm water for drinking,this water purifier addresses this need. It provides you with water at two different temperatures. One at normal 45°C and the other at 80°C.

With a weight of 15.2 kg, it measures 36.9 cm× 32.6 cm× 48.2 cm. It gives you multiple options for its placement. You can put it on a tabletop or mount it on a wall.

Like all other RO water purifiers, it offers a one-year warranty. Its green technology makes it both user and environmentally friendly.

  • It has a night assist to lead you to your water at night
  • It provides you with mineralized hot water
  • It has Advance Recovery Technology to save maximum water
  • Smart alerts for reminders
  • You can’t change TDS of output water
  • Waiting for hot water is long
  • You can fill 800ml of hot water only at a time
  • You can’t fill 1L water bottles due to its tray
  • No UV protection

10. Express Water Reverse Osmosis: Best Water Filtration System

Best RO Water Purifiers in India

If you want an economical and simple water purifier with excellent filtration, then you should consider this Express purifier. It provides you quickly with pure water.

As it uses reverse osmosis for purification, it is suitable for hard water and pesticide-contaminated water. 99.99 % of heavy metals and compounds are removed via filtration. These include lead, fluoride, chlorine, arsenic, etc. Some bacteria and viruses are also filtered out.

It has five stages of purification comprising of:

  • Sediment filter: For dust, dirt, sand, and rust
  • Carbon block
  • Granular carbon filter: to remove chlorine and organic impurities
  • RO membrane: to lower TDS and to remove lead, arsenic, chromium, fluoride, radium, etc.
  • Post activated carbon filter: Remove unwanted taste and smell

It measures 16.18 × 18.75×18.06 inches and weighs 31 pounds. This compact design makes it convenient to fit under a sink. You can use it as a free-standing product or mount it on a wall or in a cabinet.

A quick-connect tubing system marked with different colours makes it very easy to install. It can also detect leaks and stops the water flowing in case of any moisture detected on the floor.

Its simple design makes it user friendly. You can upgrade and customize it according to your requirements. If you are moving from place to place and your water quality changes frequently, then you can add or remove filters as you need.

It can produce 50 gallons of water a day. It has a higher flow rate of 0.8 gallons per minute. An adult needs approximately 0.5 to 1.5 gallons a day. This purifier has more than enough to suffice a large family of 10 or more members.

Before buying this product, make sure of its installation feasibility at your home. Your water supply should have a pressure of 40 to 80 psi. This purifier is for indoor use only. You can soften your hard water by its RO membrane.

The material of the purifier is quite sturdy. It has a brass faucet, a steel tank, and the rest of the product is made of plastic. Wastage of water is more than desired. To produce one gallon of water it drains approximately 2- 3 gallons of water.

Proper maintenance should be done to prolong its life. Change your pre-filters including sediment filter and both carbon filters, twice a year. RO membrane and post activated carbon filter are changed once a year. It provides you with one year of warranty.

This water is not suitable for aquatic life. Drain storage tank four times (8-12 hours) before using it for the first time. You can add UV filter, alkaline water filter, and others to upgrade it. For your aquarium, use a deionization filter with it.

  • Leak stop valve/switch
  • You can use it remotely, in your basement for drinking water on 1st and 2nd floors
  • Easy to set up
  • Affordable
  • Quiet
  • Water wastage is high
  • Plastic tubing cause leaks
  • You have to flush system 4 times before use
  • Changing the filters and cleaning the system is cumbersome

How to Buy the Best RO Water Purifier

In 2009, a European journal published a study regarding water purifying units. It discussed the efficiency of 8 different domestic water purification systems in India. Their efficiency was measured by their ability to remove the enteric Hepatitis E virus. Only 2 units were successful in virus removal.

How can we know that the system we are using to purify water is the right one? Does it provide complete removal of all impurities? How can we select the one that ensures our health?

We are here to give you all the insight to select the right one.

1. TDS evaluation test
Different TDS levels require different purification systems. If your water has a TDS of less than 300ppm then you don’t need to lower it any further. You should check it for biological contamination and select the purifier accordingly.

However, if the TDS is higher than 300 ppm then you need to lower it by using the RO water purifier.

2. Hard or soft water:
Mostly water of borewell, tanker or underground water is hard. While water from rain, rivers or lakes is soft water. There is no evidence of health hazards by drinking hard water. However, most hard water also contains toxic heavy metals.
So, if you have hard water with toxic compounds, select the RO purifier. If your water is soft with heavy contamination, then you should use a UV water purifier. If your water is hard with biological contamination, then a combination of RO and UV purifier is preferable.

3. Biological contamination:
Water loaded with the water-borne disease-causing microorganisms like bacteria and viruses require UV disinfection.

4. Muddy or clear water:
If your water supply has an objectionable colour then you require a filter with ultra-filtration (UF) technology. UF is used in combination with RO or UV to enhance its efficacy. Any water containing particles that make it turbid, require UF for effective purification.

5. Chlorine or no Chlorine:
Excessive chlorine gives water a bad taste or smell. Activated carbon block or granules get rid of this chlorine efficiently. If your water contains chlorine, buy a purifier that uses activated carbon as a pre-filter.

6. Storage capacity:
Consider the water requirement of your home before selecting a particular purifier. Alienate the storage capacity of your purifier with your needs.

7. Installation feasibility:
Before buying your dream-water purifier consider its installation requirements. Keep in mind its dimensions and your water supply pressure. Are you going to place it on the tabletop or mount it on a wall? Is there any electricity inlet and a water inlet near its placement?

8. Budget :
The most important one is to consider the cost of the water purifier you want to buy. If your budget is low then gravity-based water purifiers can fulfil your requirement. RO and UV water purifiers usually cost higher.

9. Comparison with other products:
Compare all the specifications of different water purifiers before selecting the one. Check for third party certifications also.


There is a ton of water purifier found in the market to know which purifier filters which substances and is best against which type of water you must know the mechanism behind the purification here are the different purification system used in the purifiers.

1. Sediment filter:

This is mainly used as a pre-filter in most purifiers. The membrane of these filters has different pore sizes varying on the type of the filter. The filter with a pore size of 1 micron resists the particles greater than 1 micron. The pore size ranges from 1 to 100 microns. The lower the size the better the filtration is and lower the flow rate. It is usually made of polypropylene or pleated polyester.

This filter is used alone in point of entry (POE) water filtration systems, or combination with other filters.

  • Affordable
  • Simple replacement by replacing the membrane
  • Range of pore sizes available
  • Cannot filter the contaminants lower than 1 micron
  • It requires other filtration systems to work effectively

2. Activated carbon block filter:

This filter uses powdered carbon held together via a binding agent. This powder has high absorption and a large surface area. These tiny pores resist any bacterial growth. This works by removing chlorine, volatile organic compounds (VOC), lead, and microscopic cysts. Any impurities greater than the pore size remain on the surface while others are absorbed. It removes ionized chlorine by attracting it to its positive surface.

  • High efficiency to cost ratio
  • Removes chlorine
  • Long life
  • Retains essential minerals
  • Little to no pH level change
  • Doesn’t need a power supply
  • Prevents growth of bacteria
  • Natural with no chemical involvement
  • Green technology
  • Requires sediment filter for effective efficiency and long life
  • Cannot remove viruses
  • Excess minerals and dissolved salts are not removed

3. Granular activated carbon filter:

It works similarly to the carbon block filter. These granules are larger than the powder. This provides weaker filtration but a higher flow rate. It is used before activated carbon block or as a point of entry (POE) filtration due to its higher speed.

  • High flow rate
  • Good filtration
  • Retains essential minerals
  • Minimal pH level change
  • Bacterial growth
  • Low filtration against smaller sized impurities
  • Water channeling

4. Reverse osmosis:

This filtration uses a semi-permeable membrane to filter water from a higher solute concentration to a lower solute concentration. This requires the use of a pump for external pressure. This removes all contaminants except volatile organic compounds (VOC), some pesticides, solvent, and chlorine.

It has a slower rate so it comes with a storage tank. Impurities retained on the surface of the RO membrane are flushed away to increase its life. Pore size can be 0.0001 microns.

  • Effective filtration
  • Lower TDS
  • Effectively filters dissolve salts, heavy metals, and some bacteria, etc.
  • Flushing of membrane givesextra-long life of 2-3 years
  • Higher wastage of water
  • Expensive
  • Slow filtration rate
  • Doesnot remove volatile organic compounds, some pesticides, and chlorine
  • Removes essential minerals
  • Lowers water pH

5. Distillation:

This process boils water and then converts vapours back into the liquid.

  • Dissolved salts, minerals, and bacteria are removed
  • No need for filter cartridge replacement
  • Slower with low output
  • Needs electrical energy
  • Removes essential minerals

6. Ion exchange:

Here water passes through an ion exchange (IE) vassal with IE resin. It has both cation and anion exchange processes. For water softening, sodium replaces calcium and magnesium ions. While for anion exchange chloride replaces arsenic, nitrate, and uranium, etc.

  • Cheaper
  • Removes inorganic impurities
  • Soften water
  • Regenerable for continuous use
  • High operating cost
  • Cannot remove microorganisms, sediments, and organic impurities

7. UV disinfection:

UV rays inactivate micro-organisms by effecting their DNA. This method removes disease-causing bacteria, viruses, protozoa, and cysts. Chlorine resistant microorganisms in municipally treated water are also removed.

  • Low maintenance
  • Remove 99.99% of microorganisms
  • Low energy usage
  • Chemical-free solution
  • Safe for environment
  • Needs electricity
  • Needs pre-filter for higher efficiency
  • Removes no other contaminants except microorganisms
  • Needs frequency monitoring for a UV lamp or light tube

8. Ultra-filtration (UF)

Here hydrostatic pressure forces water through a semi-permeable membrane. If it has 0.01 to 0.02 microns size pores then it can also remove bacteria and parasites. It has a range of 0.01 to 0.5 microns size pores.

  • Removes bacteria, viruses, parasites, and turbidity causing pathogens
  • Retains essential minerals
  • High flow rate
  • Suitable for low water pressure
  • Longlife of two years
  • Resists chlorine, no need for activated carbon filters
  • Cannot remove the taste or smell of chlorine
  • Unable to remove dissolved solids and organic contaminants like VOC and cysts.

9. Activated alumina filter

It is made of aluminium oxide. It has high absorption.

  • Removes 99% fluoride
  • Removes arsenic, selenium, and thallium
  • Can regenerate
  • Limited filtration
  • Needs regular cleaning
  • Some aluminum gets into the water if it is not properly tested

10. Ionization (alkaline ionizer)

Here it uses electrolysis to purify water.A positive and negative electrode on a low voltage plate is present. Cations go to negative electrode to produce alkaline water while anions go to positive electrode to produce acidic water

  • Anti-oxidant rich alkaline water for drinking
  • Acidic water for external domestic purpose
  • You can adjust the pH level according to your needs
  • Needs electric power
  • Weak filtration
  • Cannot remove TDS and organic impurities
  • Benefits of alkaline ionized water have no scientific evidence

Types of Contaminants present in water

A study of water quality in America took place from 2004 to 2009. Here the analysis of tap water from 20 million sources was done. The result reflected 316 total contaminants in water.

When we list water quality, India ranks 120 out of 122 countries. There is a 70% contamination of all freshwater sources. What is this contamination? Are all contaminants harmful? Which substances cause water pollution?

Anything other than water molecules is referred to as a contaminant. Do you know the four different types of contaminants in water?

1. Organic Contaminants

Water polluted with industrial waste or with pesticides through agricultural water contains organic contaminants. They are usually physical contaminants. They make your water turbid or muddy in appearance. They can be:

Pesticides : Improper handling of these chemicals makes the water prone to their exposure. They affect the chemical process of pests. If they get inside a human body, the effect their metabolism. The liver and nervous system are affected the most.

Volatile Organic Chemicals (VOC) : They include solvents and chemicals like benzene, adhesives, gasoline and fuel additives, etc. They come in drinking water by industrial waste dumping. They cause chronic effects on the kidney, liver, nervous system, and reproductive system, etc.


Emerging Organic Contaminants : They include pharmaceuticals (antibiotics, paracetamol, ibuprofen, etc.), industrial chemicals (petroleum hydrocarbons, etc.), personal care products, perfumes, and water treatment byproducts, etc.

They cause hormone imbalance and can predispose to cancer.

2. Inorganic Contaminants

They cause chemical contamination of water. They include :

Calcium or Magnesium : They can bind with carbonate or other ions to cause the hardness of the water. 300-400mg/L hardness is acceptable. Prolonged drinking of hard water with TDS>500mg/L can cause kidney stones.

Arsenic: maximum safe limit (MCL)is 0.010mg/L. Prolonged exposure causes cancer.

Fluoride: by over-exploitation of groundwater, or human-induced (medicines, etc.). MCL is 4mg/L.

Mercury: it comes in water by seepage from landfills, industries, and from agriculture. MCL is 0.002 mg/L. It damages the kidney.

Copper: it gets in water from corrosion by plumbing or natural sources. MCL is 1.3 mg/L.

Chromium: from leather or metal industries. MCL is 0.1mg/L. It affects the liver, kidneys, lungs, and skin.

Lead: from corrosion of old water systems. MCL is 0.015mg/L. it causes hypertension and affects kidneys and bones.

Antimony: from natural sources or ceramics, glass, and fireworks industries. MCL: 0.006mg/L. it increases your blood sugar and cholesterol.

Nitrate: from fertilizers or improper sewage and humans or animals waste disposal. MCL: 10mg/L. It causes low oxygen in the blood. In 2019, nitrate contaminated water of India’s 387 districts.

Asbestos: MCL:7 million fibers/liter. It increases the risk of cancer.

Selenium: MCL:0.05mg/L. It comes from electronics, photocopy, chemicals, and drugs, etc. It makes your fingers go numb and cause fatigue.

Barium: from naturally dissolving into groundwater. MCL:2mg/L. It affects the cardiovascular system.

Beryllium: Runoff from mining operations adds it into water. MCL:0.004mg/L. It affects bones and lungs and increases the risk of cancer.

Cyanide: from improper waste disposal. MCL: 0.2mg/L. It can cause death.

3. Biological Contaminants:

They include living things inside the water.

Algae : It is present in water contaminated with industrial waste. It gives objectionable taste and smell to the water. Drinking this water damages your liver and nervous system.

Bacteria : They include many disease-causing bacteria, like fecal coliform and E. coli. They can cause typhoid, cholera, dysentery, or gastroenteritis. Some harmless bacteria can still affect water by changing its taste or smell.

Protozoa : Fecal contamination of water results in water laden with protozoa. They include Giardia and Cryptosporidium. They disturb your gastrointestinal system. Nausea, vomiting, diarrhea, cramps, headaches, and fatigue, etc. are some of its effects.

Viruses : Many strains of the Hepatitis virus and Poliovirus are found in water. Their effects include diarrhea, vomiting, and abdominal cramps.

4. Radiological Contaminants:

Natural water sources moving through radioactive rocks have radiological contaminants. They include Uranium, Radium, and Radon, etc. They predispose to cancer.

Frequently Asked Questions :

Which type of water purifier is best?
The water purifier that is best for you depends on your particular water type. High TDS needs an RO water purifier. Biologically contaminated water needs UV purifier. Muddy water needs a UV+UF water purifier. For further details consult our buying guide.

Is RO better or UV?
RO is better for high TDS water, while UV purifier removes biological contamination. If you have a high TDS water with heavy contamination, select a purifier with both technologies. For details refer to the types of water purification systems.

Is drinking RO water harmful?
Reverse osmosis technique helps in the removal of excess toxic minerals in your water. Lowering the TDS of your water not below 50mg/L poses no health hazards. However, if the TDS of your water is already low, RO removes both essential and toxic minerals from your water. It is recommended to add a remineralizing filter in your RO purifier in such a case.

Can water purifier be switched off?
Yes, you can switch RO water purifiers if needed. However, you have to keep the RO membrane wet to prevent its damage. Keep your outlet and inlet pipes above the purifier to prevent drying out of the RO membrane. Flush your system for at least 10 minutes before using it again.

Can water purifier purify saltwater?
Yes absolutely. RO water purifiers remove all the dissolved salt and you can control the amount of salt in the output. However, purifiers without RO don’t have this capability.

Can water purifiers remove fluoride?
A reverse osmosis water purifier is the best one to remove fluoride. It removes all the dissolved salts and removes the hardness of the water. It can also remove bacteria and pesticides.

When to service a water purifier?
The maintenance of a water purifier is mentioned in its user manual. Generally, the RO membrane needs replacement once a year. But it may need it earlier. You can consult your purifier’s user manual for specific instructions.

When to buy RO water purifier?
RO water purifier is not for every water supply. Check the TDS of your water before buying a RO purifier. If it is higher than 300mg/L choose RO. Otherwise, UV and UF purifiers are options to consider.

When to service an Aqua guard water purifier?
Aqua guard water purifier needs servicing generally after every six months. You need to change all your filters after 1 year. Consult the user manual of your purifier for specific instructions.

Can water purifiers remove viruses?
Yes, water purifiers do indeed remove viruses. UV water purifier inactivates all the viruses, bacteria, protozoa, and cysts. RO purifier removes all viruses, microbes, turbidity, and dissolved salts.

How water purifier works?
Water purifiers have different filtration systems for different water types. RO purifiers make use of a semi-permeable membrane to filter out water. UV purifiers use ultraviolet rays to kill microbes. UF purifiers use hydrostatic pressure to filter water. For details refer to the types of water purification systems.

Why water purifier is needed?
Water purifiers are today’s need. In India in 2019, 387 districts had nitrates contaminated water. This shows only one contaminant. Hundreds of such pollutants with serious health effects are present in our water sources. They pollute our freshwater, natural sources, borewell, tankers, or municipally treated water. To ensure our and our family’s health, we need clean water by water purifiers.

Is water purifier good for health?
Yes, a water purifier removes all the harmful substances. They remove all disease-causing microbes and toxic chemicals. They certainly protect us from water-borne acute and chronic diseases and improve our health.


How much water do you drink every day? Is your water clean? Do you ingest chemicals and microbes with your water? These are important questions that need answering.

According to the Mayo Clinic, an average intake of 3.7 litres for men and 2.7 litres for women is essential. We should at least know that the 3.7 litres we are drinking contain which elements.

Knowing our water supply and making it pure for ourselves and our family is our responsibility. Know your water purifiers, buy them after careful deliberation, and maintain them perfectly.

Water is a blessing and should be given to our bodies as a blessing too.

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