Hard water filtering
Scale and soap trouble are a mineral job. Carbon will not fix them; a softener is the usual tool.
Hardness
scale, soap
Softener
ion exchange
Not taste job
carbon is different
Match the job
- Scale / soap → softener (ion exchange). See softeners.
- Chlorine taste → carbon, not a softener. See carbon.
Before you buy anything
- Descaling kettles and fixtures is free maintenance.
- Hardness is usually comfort and appliances — not a safety score on this site.
Education only — no products. Start from the problem, not the brand.