Water Softener Sizing
Water Softener Sizing Chart
Determine the proper water softener based on your hardness and number of people in your house.
Number of people in your house
|Hardness in Grains Per Gallon||1 to 2 people*||3 to 4 people*||5 to 6 people*||7 to 8 people*|
|5-10 GPG||32,000 Grain||32,000 Grain||32,000 Grain||40,000 Grain|
|11-20 GPG||32,000 Grain||32,000 Grain||40,000 Grain||48,000 Grain|
|21-30 GPG||32,000 Grain||40,000 Grain||80,000 Grain||96,000 Grain|
|31-40 GPG||40,000 Grain||64,000 Grain||64,000 Grain||96,000 Grain|
|41-50 GPG||64,000 Grain||80,000 Grain||96,000 Grain||110,000 Grain|
|51-75 GPG||64,000 Grain||80,000 Grain||96,000 Grain||110,000 Grain|
|76-100 GPG||80,000 Grain||96,000 Grain||96,000 Grain||110,000 Grain|
Determining Water Hardness
My water is supplied by my city/municipality
We recommend contacting them directly first for information about your water hardness. Most providers provide water hardness information on their website or will provide if contacted.
Request Free Water Test Kit
Learn what your water hardness is and more with our free water test kit.Request Free Kit
Ideal regeneration frequency is 5 to 7 days at 75% of total capacity. Why 75% capacity? 25% reserve capacity is necessary in case of excessive water use from time to time.
Example: 3 people (75 gallons per person per day) in a home avg. 225 gallons of water used per day with 15GPG will need a 32,000 grain system set up for 24,000 grain capacity.
Convert PPM to GPG
If you need to convert hardness from ppm to Grains per gallon (GPG) divide the total water hardness by 17.1.
Example: 200ppm of total hardness / 17.1 = 11.69 GPG
Adjust for Iron
If iron is present in your water supply please add 5 grains of hardness for every 1 ppm of iron and determine your size water softener from there.