Water softeners
The usual technology for hard water — scale, soap, and film on fixtures.
Hardness
Ca / Mg
Ion exchange
softener resin
Not disinfectant
not a taste filter
What it does
Softeners swap hardness minerals (calcium, magnesium) for sodium or potassium on a resin bed. Result: less scale, better soap performance.
What it does not do
- Remove chlorine taste (use carbon for that).
- Disinfect water.
- Fix every chemical concern — it is a hardness tool.
Upkeep
Needs salt (or potassium) and regular regeneration. A neglected softener stops working quietly.
If you want more detail
People researching units often look for NSF/ANSI 44 and read the exact claims. Softened water adds a little sodium — relevant if you track sodium closely. Education only; no products recommended.