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Plumbing

Check Toilet for Leaks

EASY10 minPlumbingPart of Summer Maintenance

Why It Matters

A leaking toilet flapper can waste 200 gallons of water per day. That is $50+ per month on your water bill for a $5 part.

Quick Guide

  1. 1

    Gather your tools and materials

    You'll need: basic tools. Materials required: Food coloring.

  2. 2

    Perform the check toilet for leaks

    Add food coloring to the tank and check if color appears in the bowl without flushing to detect flapper leaks.

  3. 3

    Verify and clean up

    Check that the work was completed correctly and clean up your workspace.

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Tools & Materials

Materials

  • Food coloring

Community Tips

WarningKasa Team

A running toilet from a worn flapper can seem minor but costs $35-50 monthly in wasted water on average; however, ignoring it for 6+ months may require replacing the entire fill valve assembly (Kohler Ingenium replacement kit, $40-65) rather than just the $8-12 flapper alone.

TipKasa Team

The food coloring test works because toilet leaks often occur silently at the flapper valve, and adding a few drops of coloring to the tank reveals even minor seepage into the bowl within 15-20 minutes without requiring dye tablets. This method catches leaks that waste 200+ gallons daily before they appear on the water bill.

Cost InfoKasa Team

Homeowners who perform the food coloring leak check quarterly catch problems at the $15-25 repair stage (new flapper or adjustment), while delaying detection by a year can escalate costs to $200-300 when mold growth or water damage to subfloors becomes involved. ---