Copper vs Alkaline Water Purifier: Two Add-Ons, Two Different Claims

Neither of these is a purification stage. On the flow diagram, both appear after the RO membrane and usually after the UV lamp: the water has already been purified, and the cartridge is deciding what goes back into it before it reaches the tap.

That framing is useful when comparing prices. You are not comparing two purifiers — you are comparing two optional post-treatments on the same purifier, and you should judge them on what they add per rupee.

Storing drinking water in copper vessels is a genuine and old Indian practice, and copper does have antimicrobial properties at the surface. The purifier version dissolves a controlled trace into water that has already been sterilised by UV and stripped by RO, so the antimicrobial argument has very little left to do.

Copper is also an essential trace nutrient, but the quantities involved are small relative to diet, and excessive copper is not benign. BIS IS 10500 sets 0.05 mg/L as the acceptable limit for drinking water. A well-designed unit doses well below anything problematic and should be able to tell you its figure; a unit whose brochure talks about copper's benefits without publishing a dosing number is selling atmosphere.

If your input TDS is above 600 ppm, the RO output is genuinely mineral-poor and an alkaline or mineraliser cartridge earns its place — you are replacing something that was removed, and you will taste the difference.

If your input TDS is 200-400 ppm, skip both and set the TDS controller to land around 80-100 ppm. You will get the taste benefit from water that was never stripped in the first place, at zero recurring cost.

Buy copper if you like the idea and the taste, and price it as a preference. It is not a health investment and no honest seller will present it as one.