Water Purifier Buying Guide India — RO, UV, or Gravity
Water Purifier Buying Guide India — how to match RO, UV, or gravity purification to your water's TDS, and the running costs no one mentions.
The single most common water-purifier mistake in India is buying an expensive RO system when your water does not need it — wasting water, stripping minerals, and paying for maintenance you could have avoided. This guide starts where the decision really begins: your water's TDS. Get that right and everything else follows.
We have researched and evaluated water purifiers to distil the decision factors below. Test your water first, then match the technology — RO, UV, or gravity — to what you actually have.
Looking for picks first? See Best Water Purifiers in India (2026).
Key Decision Factors
1. Know Your Water Source — This Decides Everything
The right technology depends entirely on your input water's TDS (Total Dissolved Solids). Before spending on a purifier, spend ₹200 on a digital TDS meter and test your actual supply — it settles the RO-vs-UV question instantly.
| Water Source | TDS Level | Recommended Technology |
|---|---|---|
| Municipal (treated) | Under 200 ppm | UV or UV+UF |
| Borewell (moderate) | 200-500 ppm | RO+UV |
| Borewell (hard) | 500-2,000 ppm | RO+UV+TDS controller |
| Unknown | Test first | Use a TDS meter |
2. RO vs UV vs Gravity — Not All Water Needs RO
RO removes dissolved salts and heavy metals but also strips minerals and wastes 60-70% of input water. UV kills bacteria and viruses without altering taste but cannot remove dissolved solids. Gravity purifiers need no electricity and suit already-treated municipal water. If your TDS is under 200, RO is the wrong choice. Compare systems across every budget in Best Water Purifiers in India (2026).
3. Storage Tank — Match to Family Size
Tanks range from 5-12 litres. A family of four drinking ~3 litres per person daily needs at least a 10-12 litre tank for drinking plus cooking. Ensure the tank is food-grade and BPA-free, and important during frequent power cuts — a larger tank keeps purified water available when the pump is off.
4. Maintenance Costs — The Hidden Recurring Expense
Filters are a recurring cost that many buyers overlook. RO membranes need replacing every 12-24 months (₹1,500-3,000), pre-filters every 6 months (₹300-800), and UV lamps annually (₹500-1,000); an annual maintenance contract runs ₹2,000-4,000. Factor this in and choose a brand with reliable local service.
5. Mineral Retention — TDS Controller or Mineraliser
RO water below ~50 ppm tastes flat and lacks beneficial minerals. A TDS controller blends back some pre-RO water to hold 60-80 ppm, and a mineraliser adds calcium and magnesium. Either keeps the water tasting good and nutritionally sensible — worth having on any RO unit.
6. Convenience Add-Ons — Beyond the Basic Purifier
If you want chilled or instant-hot water on tap, a hot and cold water dispenser pairs well with a purifier for a complete drinking-water setup — handy for families and small offices.
Common Mistakes to Avoid
Installing RO when UV is enough. If municipal TDS is under 200 ppm, RO wastes most of its input water, strips healthy minerals, and adds needless maintenance. UV is the more appropriate and economical choice.
Ignoring the maintenance schedule. Skipped filter changes turn a purifier into a bacteria trap. Set reminders, or choose a brand with proactive service, so the water stays genuinely clean.
Buying on celebrity endorsement. A brand ambassador says nothing about purification quality. Check the actual technology, certifications (ISI mark, WQA), and after-sales network in your city.
Skipping the water test. Choosing a purifier without knowing your TDS is guesswork. A cheap TDS meter removes the uncertainty and often saves you from over-buying.
Ready to See Our Picks?
Now that you know which technology fits your water, see the purifiers we recommend.
See Our Top Picks →→Frequently Asked Questions
Test your water's TDS with an inexpensive meter. Under 200 ppm, UV (or UV+UF) is enough. Between 200-500 ppm, RO+UV makes sense. Above 500 ppm, you need RO with a TDS controller. The TDS reading, not the brand, should decide the technology.
Kent and Aquaguard (Eureka Forbes) lead in RO with the widest service networks, while Pureit (HUL) offers strong value in UV and gravity systems. Whichever you pick, confirm easy filter availability and service in your city.
Purchase runs ₹8,000-20,000, with annual maintenance of ₹2,000-4,000. So the first year is roughly ₹10,000-24,000, and subsequent years ₹2,000-4,000 for filter replacements and servicing.
RO water with TDS kept at 60-100 ppm via a TDS controller is safe. Very low-TDS water (under 30 ppm) can leach minerals and is not recommended for infants, so always check the output TDS on an RO system.