Sizing Your Purifier: Why TDS Is the Only Starting Point
Many Indian households blindly install RO purifiers on municipal water, throwing away 65% of perfectly clean water down the drain while stripping natural calcium and magnesium.
Input Water TDS & Purification Technology Match
| Input Water Source | Input TDS Level | Required Purification Tech | Water Wastage | Recommended Setup |
|---|---|---|---|---|
| Municipal / DJB / BMC | 50 – 250 ppm | UV + UF + Sediment + Carbon | 0% (Zero Wastage) | Kent Maxx / AO Smith UV |
| Mixed Water (TDS 250-500) | 250 – 500 ppm | RO + UV + TDS Controller | ~50% Rejection | Eureka Forbes / Livpure |
| Borewell / Deep Ground | 500 – 2000 ppm | Heavy-Duty RO + UV + Mineralizer | ~60% Rejection | AO Smith Z8 / Kent Grand Plus |
| High Fluoride / Arsenic | >1500 ppm | Commercial Dual RO + Post-treatment | ~65% Rejection | Specialized High-TDS RO |
Key Decision Takeaways:
- The TDS Meter Test First: Buy a ₹250 digital TDS meter from Amazon and test your tap water before ordering a purifier.
- TDS Controller / Modulator: Mixes a fraction of UV-treated water with RO-treated water to maintain healthy drinking TDS between 100–150 ppm.
- Stainless Steel Tank vs Food-Grade Plastic: Stainless steel water tanks prevent algae formation and secondary bacterial contamination in stagnant storage.
Practical Rupee Cost Breakdown:
- UV+UF Purifier (Municipal Water): ₹6,000 – ₹9,500.
- RO+UV+Mineralizer (Borewell Water): ₹12,000 – ₹18,500.
- Annual Maintenance & Filter Cartridge Replacement: ₹2,500 – ₹4,500/year (Sediment, Pre-carbon, RO Membrane, Post-carbon).
What to Check Before Buying:
- Ensure the unit has a pre-filter bowl outside the body to trap heavy rust and sand before it ruins the internal pumps.
- Confirm if the brand requires proprietary locked RFID filters or accepts universal replacement membranes.
