Book 30, Question 88
How does a water softener work?
A water softener has a tank full of tiny resin beads that attract calcium and magnesium.
As hard water flows through, those minerals stick to the beads, and the beads release sodium in exchange. Over time the beads fill up, so the machine flushes them with salty water to recharge. The water that leaves is softer, and soap lathers better.