top of page

How to Determine the Right Size Water Softener for Your Home

Learn how to properly size a water softener system for your home based on daily water use, hardness levels, and treatment needs. Use our grain capacity formula to determine the right softener size and salt tank.
Learn how to properly size a water softener system for your home based on daily water use, hardness levels, and treatment needs. Use our grain capacity formula to determine the right softener size and salt tank.

If you live in an area with hard water, installing a water softener is one of the best investments you can make for your home. Hard water contains high levels of calcium and magnesium ions that can lead to scale buildup on fixtures and appliances, reducing their lifespan. Hard water also makes it difficult to lather soap and shampoo properly. The solution is to "soften" your water by removing these mineral ions through a process called ion exchange.

But how do you know what size water softener you need? Choosing the right water softener capacity or "grain capacity" for your household is important to ensure optimal performance. Here's a step-by-step guide to help you determine the ideal water softener size for your home.

Calculate Your Daily Water Usage

The first step is to estimate your household's daily water usage, as the softener capacity will need to handle the entire volume of water used daily. Take into account all water uses including:

  • Showers, faucets, toilets - number of people in the home and average daily usage

  • Laundry - loads per week

  • Dishwasher - loads per week

  • Irrigation system (if applicable) - gallons used for watering lawn/garden

To determine gallons used, review your water bill for average daily usage. Or install a water meter on your main supply line for a week to measure actual usage.

As a general guideline, the average household uses 50-80 gallons of water per person per day.

Determine Your Water's Hardness Level

The hardness level of your water, measured in grains per gallon (gpg), determines how much calcium and magnesium needs to be removed. Hardness levels range from 1 to 50+ gpg.

To find out your water hardness:

  • Check your last water quality report from your local water company

  • Use a water hardness test kit

  • AquaLux Water Softener offers free water testing to assess hardness - click here to schedule

Higher hardness levels require a larger softener size and more frequent salt regenerations. For reference:

  • 0-3 gpg is considered soft water

  • 3-6 gpg is moderately hard

  • 6-9 gpg is hard

  • Over 9 gpg is very hard

Calculate Softener Capacity Needed

Once you know your household’s daily water use and the hardness level, you can determine the minimum grain capacity required using this formula:

Grains of hardness to be removed daily = Water used daily (gallons) x Water hardness level (gpg)

For example:

  • 4 people in the home using 300 gallons per day

  • Hardness level of 20 gpg

Daily grains to be removed: 300 gallons x 20 gpg = 6,000 grains

Therefore, this household needs a softener with at least a 6,000 grain capacity to adequately treat their entire water supply.

The AquaLux line of water softeners from Aqua-Wise Water Treatment Solutions has a range of capacities to handle any home's needs.

Larger households or those with extremely hard water may need an even higher capacity 80,000 or 100,000 grain system. Our water treatment experts can help determine the ideal softener.

Size the Salt Brine Tank

Along with grain capacity, the size of the brine tank that holds the salt pellets or crystals is another key consideration. The brine tank should be large enough to hold at least 1-2 weeks supply of salt.

As a general guideline for sizing:

  • 10,000 grain capacity softener - 250 lb salt tank

  • 20,000 grain capacity - 350 lb salt tank

  • 30,000+ grain capacity - 500+ lb salt tank

The amount of salt used per regeneration depends on:

  • Water hardness - the harder the water, the more salt needed

  • Water usage - higher water use means more frequent regenerations

For moderately hard water (10 gpg), expect to use 10-15 lbs of salt per regeneration for a 20,000 grain softener. At this rate, a 350 lb salt tank provides 1 month supply for average households before needing to refill.

Choose the Right Softener System

Once you've determined the right capacity and tank size, it's time to select the right system. Aqua-Wise offers a full range of water softeners to meet any household's needs:

  • AquaLux - Highly efficient and fully adjustable metered softeners

  • AquaSmart - Value line softeners with user-friendly controls

  • Fleck - Custom softeners built on industry-leading Fleck valves

Our water treatment specialists can help you select the ideal system based on your water quality, household size, and budget. All our systems use high capacity resin media that can remove up to 30,000 grains of hardness per lb of resin for maximum efficiency.

Professional Installation Available

Proper installation is key to ensuring your water softener performs as expected. Aqua-Wise offers full-service installation of water softeners throughout the Tampa Bay area. Our certified technicians will handle all aspects of the installation including:

  • Bypass valve setup for easy maintenance

  • Adjusting settings based on your household parameters

  • Programming the system controller

  • Ensuring correct brine draw and backwash cycles

  • Providing a full operational tutorial for homeowners

We also offer expert maintenance, parts, and service for optimal softener performance. Contact us today to learn more about our water softener installation and support services.

Soften Water for Better Living

Installing the right sized water softener provides wide-ranging benefits including:

  • Smoother, softer skin and hair

  • Cleaner laundry without detergent buildup

  • Sparkling dishes without spots

  • Scale-free fixtures and appliances

  • Safer water for drinking and cooking

  • Longer system lifespan for water heaters, pipes, and more

Remove the hardness once and for all with a properly sized water softener from Aqua-Wise Water Treatment Solutions. Schedule your free water test today to get started!

We also offer other water treatment solutions including reverse osmosis drinking water systems, whole house filters, iron & sulfur removal, and commercial treatment. Learn more at



Rated 0 out of 5 stars.
No ratings yet

Add a rating
bottom of page