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Strong fit for buyers who want true soft water and app-based metered regeneration.
RKIN sells WS9 for 1–3 bathrooms, WS10 for 4+ bathrooms and larger configurations. The system uses ion-exchange resin, a brine tank and a Bluetooth-enabled metered control valve that regenerates based on water usage rather than only a fixed timer.
Why it stands out
True hardness removal, smart valve, chlorine-resistant resin media, assembled in the USA, lifetime warranty on tanks and parts, and 1-year satisfaction guarantee.
What you accept
Salt bags, regeneration wastewater, drain connection, periodic maintenance and sodium/potassium exchange into softened water.
How the smart valve changes ownership
The RKIN valve monitors water usage and regenerates when needed, which can reduce unnecessary salt and wastewater compared with a crude fixed-day schedule. It also provides app-based setup and monitoring.
Who should choose WS9 vs WS10?
Bathroom count is a useful first screen, but hardness level and simultaneous flow matter. A three-bathroom home with very hard water and high peak demand may need more capacity than a typical WS9 buyer. Use a hardness test and actual household demand before ordering.
What it does not remove
A softener handles hardness. It is not a carbon filter for chlorine, PFAS or VOCs. If city-water chemicals are also a concern, pair softening with an appropriate filtration stage rather than expecting one tank to do both jobs.