Increase detergent slightly if you have hard water

If your household has hard water (high mineral content), increase your detergent dose by about 25-50% above the standard recommendation, or add a water-softening booster like washing soda or borax.

Why It Works

Hard water contains calcium and magnesium ions that bind with detergent molecules, neutralizing them before they can clean. This means a portion of your detergent is "wasted" on mineral binding rather than lifting soil. Compensating with extra detergent or a water softener ensures enough active surfactant remains for cleaning.

Tips

• Over 85% of U.S. households have some degree of hard water
• Water hardness test strips are inexpensive and available at hardware stores
• Adding 1/2 cup of washing soda (sodium carbonate) per load is a low-cost alternative to using more detergent
• If you notice white residue on dark clothes or mineral buildup in your machine, hard water is likely the cause