Best RO water purifiers for borewell and high-TDS water
By Sadguru Research & Analysis Laboratory · 23 October 2026
Borewell and tanker water in and around Kolkata often has high dissolved salts, hardness and iron. That is the one situation where an RO purifier earns its price. Here is how to decide, and which premium models we would shortlist.
As an Amazon Associate we earn from qualifying purchases. Product links open Amazon.in. Prices and availability are shown on Amazon.
First, know your numbers
IS 10500 sets an acceptable limit of 500 mg/l for total dissolved solids and 200 mg/l for total hardness (as CaCO3). If your borewell tests above these, RO is the practical way to bring them down at home.
A TDS meter gives you a first reading in seconds. A full drinking water test also checks iron, nitrate, fluoride, arsenic and bacteria, which tells you whether you need more than RO alone.
What to look for in a premium RO
A TDS controller or mineral stage, so the output is not stripped to near-zero TDS. UV or UF after the membrane, to deal with germs from the storage tank. A food-grade or steel tank big enough for your family. And a service network that actually covers your area.
KENT Grand RO Water Purifier
A dependable wall-mount RO for high-TDS borewell and tanker water, with a TDS controller to keep some minerals.
Lab note: Ask the installer to measure your input TDS and set the output between about 80 and 150 ppm.
Check price on AmazonKENT Supreme Plus Alkaline + Copper RO
High-capacity RO with an alkaline and copper stage, for families on hard or salty water.
Lab note: The alkaline stage nudges pH up slightly; it is not a medical treatment.
Check price on AmazonPureit RO + UV + MF Copper + Mineral (8 L)
Large-tank RO for bigger households that draw a lot of water at once.
Lab note: Change the pre-filters on time; a choked pre-filter shortens membrane life.
Check price on AmazonAquaguard Delight Aquasaver RO+UV+UF+MC
RO with a water-saving design, a good fit where every litre of reject water matters.
Lab note: Collect the reject water for mopping or plants.
Check price on AmazonAfter installation
Measure output TDS every month: a rising number means the membrane is wearing out. Once a year, send the purified water for a coliform and E. coli test. A purifier that has not been serviced can harbour bacteria in its tank.
Common questions
Is RO water safe to drink every day?
Yes, when the output TDS is kept at a sensible level (roughly 80–150 ppm) and the purifier is serviced on time.
Does RO remove arsenic?
A good RO membrane removes most dissolved arsenic, but confirm with a lab test of the purified water if your area is known for arsenic.
Test before you spend
A laboratory report tells you exactly what your water or food needs, so you buy the right equipment once. We test water to IS 10500 and food to FSSAI standards, with sample pickup across Kolkata.