®Tap water usually meets the standards when it leaves the plant, but "water at the tap" still travels through the pipe network and the building's secondary supply, so what ends up in your glass is shaped by everything in between.
Common risks with tap water
- Ageing pipes and building water tanks can cause secondary contamination;
- Disinfection leaves residual chlorine and small amounts of by-products;
- In some areas the water is hard, with noticeable taste and scaling.
Common filtration methods
- Activated carbon: improves taste and removes residual chlorine and odours; does not remove dissolved salts;
- Ultrafiltration (UF): removes particles, bacteria and some microorganisms while keeping minerals;
- Reverse osmosis (RO): removes most dissolved substances, minerals included, producing water close to pure;
- Softening: removes calcium and magnesium to prevent scale, mostly for water-using appliances and generally not for direct drinking.
TDS is a common misconception
TDS only reflects the amount of total dissolved solids; it does not indicate safety. Pure water has a very low TDS, but low TDS does not mean healthier, and a high TDS is not necessarily harmful. Choose filtration by looking at local water quality and your own needs first, then pick the technology.
Replace cartridges on time
Ultrafiltration and activated carbon cartridges are usually replaced by throughput or by period (typically 6–12 months), while RO membranes last roughly 2–3 years. A spent cartridge not only stops working, it can become a new source of contamination.