Find how many grains of hardness your household removes each week and how long a unit will last between regenerations.
How it works
People times gallons per day times grains of hardness gives daily grains. Divide softener capacity by that to see days between cycles.
Before you order
- Get hardness from a recent test or your water supplier in grains per gallon.
- A longer cycle uses salt more efficiently at the unit's lower salt settings.
- Iron can foul the resin, so test for it before choosing a unit.
Common questions
How do I convert ppm to grains?
Divide ppm of hardness by 17.1 to get grains per gallon.
Should I include iron?
Add it only using your softener maker's method, since published allowances vary.