Written by: Subhasish Adhikary

Water Purifier Buying Guide: How to choose the right one?

Developing countries in Asia like India and the majority of African countries where the common population has no access to clean and safe drinking water.

It is a matter of great concern that these people are getting or are not getting ill due to water-borne diseases like diarrhea, cholera, typhoid, amoebiasis, acute gastrointestinal illness, etc.

Therefore a water purifier is a necessary item to have in the household for obtaining portable, pure, and safe drinking water for these people who face this problem each and every day in their life.

Thus water purifiers are an important thing to have, and the thing is that the use is not limited to domestic households only, but also have good applications in offices, factories, hospitals, etc.

In this water purifier buying guide, I’ll provide you a walkthrough on safe drinking water standards, different types of water purifying machines, and how to choose the ideal water purifier for your home based on your requirements.

Water is an essential component of our daily lives, and it is crucial to ensure that the water we consume is clean, safe, and free of contaminants.

With the rise in water pollution levels and increasing health concerns, investing in a water purifier for your home has become more important than ever.

However, with so many types and models of water purifiers available in the market, it can be overwhelming to choose the right one for your needs.

In this article, we will provide you with an essential water purifier buying guide for your home.

We will cover the different types of water purifiers, their features, and factors to consider before making a purchase.

By the end of this guide, you will have a better understanding of the various options available and be able to make an informed decision that best suits your requirements.

Before diving into more in-depth concepts let us first make ourselves more familiar with some of the important related factors that will help you understand more about the water quality, source of drinking water, and type of water factors that influence the selection of the perfect water purifier.

Importance of safe drinking water

Water is not just for drinking that makes us quench our thirst, it is responsible for the function of other vital processes in our body that has a direct impact on living a healthy life.

Characteristics of drinking water – what should it contain?

Optimum pH

Your drinking water should have a neutral pH of 7 that is not acidic nor alkaline. If your water is found to be acidic then it will be detrimental to your health.

Our body produces wastes that are acidic in nature and water helps to balance the accumulated acids in our body.

Major diseases like cancer, arthritis, osteoporosis, etc are due to this acid accumulation.

That is why you may know or you have a habit of drinking plenty of water in the morning immediately after waking up from bed, the reason?

Simple water helps to flush the excess acids that have accumulated overnight from the body.


Water with antioxidants is very helpful in preventing potential metabolic syndrome among others. Oxidizing has adverse effects on our cells. Antioxidants in food helps in preventing it from further damaging the tissues.

Note that not all drinking water has an antioxidant nature.

Read more: https://dm5migu4zj3pb.cloudfront.net/manuscripts/112000/112869/JCI87112869.pdf


Our drinking water is supposed to have many valuable minerals & nutrients like calcium, magnesium, potassium, etc. And also other trace elements.

Minerals like calcium & magnesium get more absorbed in our body through water than food. All these minerals are mainly found in underground water reservoirs.

Mineral Composition of natural fresh water
Mineral Composition of natural fresh water

For more info, refer to this publication by WHO:

Contamination free

Water can get contaminated with many things, this is due to the source of water from where it is coming. Contamination of water is classified into 4 categories.

Physical – This refers to mainly organic sediments like muddy water.

Chemical – Water gets contaminated with chemical compounds like pesticides, bleach, etc. This happens when rainwater flows from cultivation fields to nearby water sources or factories and releases untreated water waste to nearby rivers or seas.

Biological – As the names suggest, it is the contamination of bacteria, fungi, and algae.

Fact: There can be more than 1500+ contamination in one glass of water depending on the water source. Our drinking should be free of all impurities.

Microbiologically pathogen-free

As per WHO guidelines, water should be safe to drink if it’s free from any pathogens. Water easily gets contaminated with biological elements if there is a leakage in water pipes.

Water Purifier Buying Guide: How to choose the right one? 1

I hope I’ve been able to give you a basic idea of drinking water standards, Now we’ll move towards the water purifying process that is available in the market.

Impurities in drinking water come from the very own water source

Our source of drinking water comes from the municipality, groundwater, bore well, or multiple sources. Each of these sources contains different levels of contamination & in the TDS level.

Here is a new term TDS, you’ll read this term everywhere. I’ll explain it to you below.

What is TDS?

The full form of TDS is Total Dissolved Solids. It is measured in parts per million, PPM.

This is a laboratory factor/aesthetic value, which is used to determine the amount of total dissolved solids in water. TDS elements are both organic & inorganic substances like calcium, magnesium, potassium sodium, carbonates, nitrates, chlorine, and iron, etc.

These solids get in the water in two ways, 1. Natural causes 2. Because of human interference.

Water from underground reservoirs has only useful minerals as TDS, whereas open water sources may have harmful TDS contamination mentioned above.

Is High TDS harmful?

Well, it’s tricky because a high level of TDS generally doesn’t mean it is harmful to drink [up to 1200 TDS, water is drinkable, though not at all recommended].

But if it’s contaminated with harmful elements then it’s preferable to purify the water before drinking!

Water can have high amounts of minerals such as TDS which goes up to 2000 in some water sources. Usually, people refer to drinking water which has a TDS range of 100-900.

TDS also influences the taste of the water if it’s very low. It tastes bitter and is unpleasant to many.

But consuming water with highly elevated levels of TDS i.e. more than 700 ppm may lead to health issues and will increase the chemical count in the body.

By the way, BIS i.e. Bureau of Indian Standards has stated that water having TDS of more than 500ppm is not fit for drinking at all whereas the WHO states TDS in water above 300 is not fit for drinking.

Read more about TDS here: http://www.who.int/water_sanitation_health/dwq/chemicals/tds.pdf

The main objective of water purifiers is to lower the elevated levels of TDS in water and make it fit for consumption.

Types of Drinking Water Sources

Groundwater: They have a TDS level of 200-2000 ppm.

Municipality Water: They have a TDS level of 100-300 ppm.

Multiple sources: It has a TDS range of 1-2000 ppm.

Water Purifier Buying Guide: How to choose the right one? 2
Image source: ResearchGate

The source of drinking to come to home is the first factor to consider before purchasing a water purifier.

Continue reading to know why.

Well, you’re almost halfway there in the water purifier buying guide for your home.

It’s time to discuss the filtration/purification methods that are widely used.

Types of Water Purifiers based on Filtration methods

Know more about the latest type of water purification methods that are available in the market right now.

Gravity Based/Ultrafiltration (UF) Water Purifiers

Water Purifier Buying Guide: How to choose the right one? 3

These are basically non-electric water purifiers. Gravity based water purifiers use pressure filters or Ultrafiltration techniques to purify water.

Know more about the ultra-filtration process.

These are very cheap to buy but are not that handy in removing all impurities from the water. They cannot remove dissolved solids, bacteria, and viruses.

They are useful only for municipal water where the TDS is generally between 100-200 ppm. So if your drinking water comes from the municipality then you can go for these types of purifiers.


Works without electricity

Removes the cysts, sand & mud from the water

Good for purifying municipality water.


Unable to remove any biological elements like viruses & bacteria.

Ultraviolet (UV) Purifiers

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Ultraviolet water purifiers are the basic ones in terms of electric water purifiers. They are just one step ahead of gravity purifiers.

These are also inactive against dissolved solids, they just disinfect the water but do not remove the sterilized microorganisms from the water.

But they effectively remove protozoans, viruses, bacteria, cysts, and chlorine.


Makes the microorganism present in the water inactive

Removes cysts.

Doesn’t alter the water chemically

Good for TDS below 250


Cannot remove the killed microorganisms

Doesn’t remove any organic or inorganic particles.

This is recommended if your water source is municipal water and you want to upgrade from gravity-based purifiers. Not recommended for water whose TDS is above 300.

RO (Reverse Osmosis) Water Purifiers

KENT Grand 8-Litres Wall-Mountable RO - UV UF - TDS Controller

This is the most effective water purifier of them all. They remove the hardness of water and make it fit for consumption.

RO which is the short form of Reverse Osmosis is the opposite of Osmosis which is used by plants for the intake of nutrients.

The RO process works in this way, it pushes down water through a semipermeable membrane to remove large quantities of impurities from the water.

Water Purifier Buying Guide: How to choose the right one? 5
Image Source: clearchoicewaterfilters.com.au

Learn more about Reverse Osmosis here: https://puretecwater.com/reverse-osmosis/what-is-reverse-osmosis


Most effective water purifier

Improves the taste of water

Remove impurities


RO water purifiers waste a considerable amount of water than any other water purifier, they waste approx 3 liters of water to purify 1 liter of water.

Another thing I’d like to mention is the two types of water that are available in most parts of India.

Also Read: RO vs UV vs UF Water Purifiers – Which is the best?

Check out the best water purifier in India for home

Hard water

Hard water contains high concentrations of minerals, especially calcium, magnesium, and sometimes iron. Consumption of hard water can lead to certain diseases. 

The TDS of hard water is more than 450. Therefore to make it fit to drink you’ll need RO water purifiers in this case.

Soft water

Soft water is described as water having less to no dissolved salts like calcium, iron, or magnesium. TDS of soft water is generally between 100-300. Gravity-based filters and UV filters are best for soft water.

Now time to sum it up! You have come all the down. Read the checklist for buying a water purifier for home written below.

7 Key things to keep in mind before purchasing a water purifier:

Water source

As discussed earlier the important thing to consider before buying a water purifier is to take into account the source of your drinking water at home.

If its municipality water, consider a gravity-based or UV water purifier machine for your home.

If it’s from other sources where the chance of TDS is high you have only one option and i.e. going with RO purifiers.

Storage capacity

You need to look at your family’s water requirement too, this will help you to choose the water purifier with the ideal storage. This will in turn save you some money too. Buying a water purifier with more storage will also occupy good space too.

Also if there are power cuts or the water supply is not that great in your locality then please go for a larger storage model that will help you overcome the crisis.


This again purely depends upon your water TDS level. RO is good up to 600-900 TDS range, but if the TDS is much higher then multi-step purification water purifiers can be a great choice for your home needs.


Depending on the need the cost of water purifiers will increase. Low cost as gravity purifiers, mid ranges is UV models and RO starts from Rs 7000 in India.

Mineralize feature

When the water goes through an extensive purification method, it loses all of it or says the majority of its minerals & nutrient content. Some water purifiers contain mineralized features, i.e. it adds the lost minerals back into the water.

I hope you’ll have heard the term mineral water as advertised by brands like Bisleri? Well, this is the same type of water that you’ll get from these purifiers.

You may be interested in: Alkaline Water Purifiers: All You Need To Know

Annual maintenance

This is a tricky part, maintenance cost for higher-end models is costly. If the water quality is poor then you need to replace the filters at least once per year. Generally filters price range from Rs 3000-8000 in India. For UF/Gravity-based models the filters cost around 300-500INR.

For normal maintenance the service charge for water purifiers is on the higher side, I have a Livpure pep+ model and the company charges rs700 approx for each time their technician visits.

So overall AMC will cost your around 4000-5000/year writing from my own experience.


Most of the leading companies provide 1 year of warranty but now some of them also give you the option of joining their so-called membership programs/maintenance program where you need to pay some extra bucks for extending the warranty of the product.

TDS controller

With a TDS controller, you can control the taste of the water. The only drawback is that these types of purifiers are costly.

Tips: Buy a TDS meter to check the TDS of your home drinking water. It will help you buy an accurate water purifier for your home. Refer to the TDS chart below.

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Some Commonly Asked Questions

How to choose a water purifier in India?

There are things we need to keep in mind before purchasing a water purifier. For example, the source of your drinking water, TDS, Cost, etc.

Which water purifier should I buy for small domestic use?

If your drinking water has a lower TDS count then gravity-based non-electric or for a little bit for safety a UV purifier will do the job.

Which purifier is good for your health: RO or UV?

No doubt RO water purifiers are the best as they, not only remove the impurities present in our drinking water but also improves the taste of water.

What is the maintenance cost for a UV+UF water purifier per year?

In my opinion, the annual maintenance cost of basic UV+UF models will be less than 3000INR  filter change depending on your home water.

What is the annual maintenance cost (AMC) for an RO water purifier?

Well, it is costly, it will be around 4500/year that too depends on usage & water quality. If any major part like filter needs to be changed then the cost will go up. It will be wise to opt for the company’s extended warranty schemes.

How much water is wasted during the purifying process?

Well for standard models for every liter they purify the machine throws out 650ml of water. So don’t waste that water use it for other household purposes.

Final Words

In conclusion, investing in a water purifier for your home is a crucial step towards ensuring that the water you consume is clean and safe for your health.

With so many types and models of water purifiers available in the market, it is essential to consider several factors before making a purchase.

In this essential water purifier buying guide, we have covered the different types of water purifiers, their features, and the factors to consider before making a purchase.

By considering these factors, you can make an informed decision that best suits your needs and requirements.

Remember to choose a reliable and reputable brand, and consider the capacity, filter type, maintenance, and budget.

With the right water purifier, you can enjoy clean and safe drinking water for you and your family.

Well, my research data ends here. I hope I’ve been able to provide you with an essential water purifier buying guide that describes each and everything that you need to know before purchasing a water purifier.

If I missed anything or have provided any misleading information, please feel free to correct me by commenting on this post.

And if you find this guide useful then don’t hesitate to share this with your friends & family.

Photo of author

Subhasish Adhikary

I'm constantly in search of the latest gadgets & technology news that I can share with you. In my meantime, I blog on topics ranging from digital marketing, online business, startups to tech gadgets.


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