As the pollution in our environment increases so does the level of toxic chemicals in our water. These toxic chemicals are dissolved in water and require a much advanced level of technology to purify and remove them.

This has resulted in the market being filled with water purifiers that use new and advanced technologies like RO, UV and UF methods. Some water purifiers even use a combination of two or more methods to ensure safe and healthy drinking water.

Therefore, if you are looking to buy a water purifier, then you need to figure out which one of these technologies works best to purify the water. In this article we will answer this question in a simple manner and help you find out the most suitable purifier for your household.

What is an RO Water Purifier?

RO Water Purifier

RO stands for Reverse Osmosis. This purifier uses the process of osmosis to purify the water.

Osmosis is a very commonly occurring process in nature. This is described as the process in which a weaker saline solution will automatically move towards a stronger saline solution nearby. This process is reversed in RO purifiers to get purified water. Let us understand how that is done;

The process is possible due to the presence of a reverse osmosis membrane in the purifier. This membrane is a very thin membrane that allows the movement of water but not the dissolved salts. Unlike osmosis, reverse osmosis requires external pressure.

External pressure is exerted on the contaminated/salty water to force the water through the thin membrane and leave the contamination behind. This pressure is needed to overcome the natural osmosis tendency of the water. The amount of pressure applied will depend on the level of contamination/salinity in the water.

Advantages:

  • This method removes 99% dissolved salts, particles, organics, colloids, bacteria and pyrogens.
  • Comes with multiple filters such as sediment filter, carbon filter etc along with the reverse osmosis membrane to give the maximum purification

Disadvantages:

  • It cannot remove 100% contamination because the contaminants are removed by their charge and size. This type of purifier can remove contaminants with a molecular weight of 200. Anything below that will not be removed effectively.
  • Gasses like CO2 etc., will still be present in the water because of their low charge.
  • It wastes water as instead of trapping the contaminants it drains out the contaminated water out of the purifier.

Suitability:

  • You are very concerned about the purity of your water and want the most efficient purification available in the market.
  • You are not concerned about the high operating and maintenance cost.
  • Water wastage is not an issue
  • You are unsure of the TDS level of the water in your area.

What is a UV Water Purifier?

UV Water Purifier

UV water purifiers use ultraviolet rays to kill the bacteria and germs present in the water. Unlike RO purifiers, they do not have any filters or membranes to help them filter the contaminants. This type of water purifier is highly efficient in killing disease-causing germs and bacteria.

The purifier works by exposing the microorganism to UV rays which attacks their DNA and prevents them from reproducing and causing harm to your body.

Advantages:

  • The UV treatment does not give off any weird taste or smell to the water
  • Very beneficial for areas prone to water-borne diseases cholera, typhoid, diarrhea etc.

Disadvantages:

  • The main disadvantage of a UV filter is that it cannot remove dirt, dust and other particulate matter that are present in the water. Even the body of dead germs and bacteria remain in the water after UV purification.

Suitability:

  • If the TDS level of your water is less than 500 then UV purifiers will be good for you.
  • Such purifiers are great for households where the water is coming from a city municipal tank as this water is already cleaned for sediments, dirt etc.
  • These purifiers also work great if they are accompanied by some other purification methods.

What is a UF Water Purifier?

UF Water Purifier

UF stands for Ultrafiltration, which is the technology used in a UF filter. In this type of water purifier, the water is made to pass through a thin membrane that filters out all the germs, bacteria, impurities etc. The membrane is generally 0.02 micron in thickness. It is also very fine so that only water and dissolved minerals can pass through it.

Advantages:

  • Doesn’t waste any water like RO water filters which makes it eco-friendly
  • This type of filter also preserves the essential mineral and nutrients present in the water
  • They are cost-effective
  • This type of purifier does not need electricity to operate

Disadvantages:

  • It cannot remove dissolved particles and solids from the water. If you live in an area where the TDS is high, then this purifier is not suitable for you.

Suitability:

  • If you are worried about water bills or water conservation then this is perfect for you
  • If you prefer your water to retain the beneficial minerals and vitamins then this is the kind of purifier you should go for.
  • If you either do not have a plug point in your kitchen or want to save on your electricity bill, then also this will be suitable for you

Difference Between RO VS. UV. UF Water Purifiers

ROUVUF
This wastes waterDoes not waste any waterDoes not waste any water
Requires electricity to operateRequires electricityDoes not require electricity
Filters out bacteria, viruses and germs along with dust, debris and other particlesFilters out bacteria, viruses, germs, pathogens and all kinds of microorganisms but does not remove particles such as dirt, debris etc.Filters out bacteria, viruses and germs as well as dust, dirt etc.
Filters and purifiesOnly purifies, does not do any filtrationFilters and purifies up to a certain extent
Removes dissolved ions, salts & minerals (both good & bad)Does not remove dissolved ions or minerals(both good and bad)Does not remove dissolved ions or minerals(both good and bad)
Can remove 90% TDS in the waterDoes not work against TDSDoes not work against TDS
You need to replace the filters annuallyYou need to replace the UV lamp once every yearYou need to replace the water filter once every year
RO VS. UV. UF Water Purifiers

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Which one Should you Choose?

Your choice of water filter should depend on some important factors. We have listed main things you should consider before deciding on which one of the three water purifiers you should purchase:

1. TDS

TDS stands for Total Dissolved Solids. This represents the number of dissolved minerals, salt and other particles that are present in the water. These dissolved solids can be both good and bad for health. But to be on the safe side, it is preferred to have as low TDS in your water as possible.

The only purifier amongst the above-mentioned ones that work against TDS is the Reverse Osmosis or RO purifier. It is said to be the most efficient water purifier as it works against the majority of pollutants that are found in the water.

If the locality you live in has high TDS water, then the RO purifier is a clear choice for you. If you are not sure about the TDS level in your water content, then also we would suggest you go with RO purifiers just to be on the safe side.

2. Water Wastage

Even though RO filters can purify the water very efficiently, one of the major disadvantages that they face is that they waste a lot of water. In a RO purifier, the water is divided into two streams, one in the clean, purified water and the other in the polluted and contaminated water. This contaminated water gets discarded from the purifier which causes significant water wastage.

If you are worried about water wastage then you might want to consider either UV or UF filters. Alternatively, you can also collect this contaminated water and use it for other non-essential purposes such as watering the plants etc.

3. Microorganism and Bacteria Removal

This factor is quite important as this prevents you from harmful diseases like cholera, typhoid etc. If the water to your household comes from the government/municipal tanks, then you generally do not need to worry about this as the water is treated to kill harmful microorganisms.

Even then, if you want to take extra precautions against these bacteria and pathogens the UV purifier is the most suitable water purifier for you as this directly damages the DNA of the microorganism and prevents them from multiplying.

If the water to your household comes from an unregulated place then it is crucial for you to have UV filtration in your purifier to protect you against the disease-causing microorganisms.

4. Maintenance

Most water purifiers require you to replace and clean the filters once in a while. This is an additional cost that you have to bear after purchasing the purifiers.

RO purifiers have multiple filters and each of these filters needs to be replaced once every year at most. The total cost of this replacement can range from Rs.1000 to Rs.6000 depending on the area you live in.

On the other hand, UV and UF purifiers have a comparatively lesser maintenance cost. For UV purifiers, you need to replace the UV lamp once every year at least. The cost of this UV lamp can range from Rs.200- Rs.500. Similarly, to replace the filter of UF purifiers you need to spend Rs.500 to Rs.1000. This replacement has to be done annually.

5. Electricity consumption

Both UV and RO purifiers require electricity to operate. The power consumption of a filter is not high but this might be important if your kitchen does not have enough electrical plug points and you need your purifier to be placed there.

The Final Call:

It is our advice that you go for a water purifier that has more than one technology to disinfect the water, this can be either RO+UV or UV+UF or the best will most certainly be if you can find all three technologies in a single purifier. However, if you have to choose between the three, we would recommend you go with the RO water filters.