New Delhi, Dec. 5 -- Living in a high AQI zone means you're already exposed to polluted air, making clean drinking water even more essential. But most families forget that water quality varies drastically across cities and choosing the wrong purifier can either fail to protect you or cause unnecessary water wastage.

Before buying any purifier, the most important step is to check your water quality. The technology you choose should match the water that comes into your home, not the marketing claims of a product.

Total Dissolved Solids (TDS) tells you how many dissolved salts, minerals, and heavy metals are present in your water.

Why this matters:

Your entire purifier choice, RO, UV, UF, or a combination, depends on this TDS number. A s...