Soak grout with oxygen bleach solution

Dissolve powdered oxygen bleach (sodium percarbonate, sold as OxiClean or similar) in warm water per the product directions. Apply generously to grout lines and let it soak for 15-30 minutes, then scrub with a stiff brush and rinse thoroughly.

Why It Works

Sodium percarbonate breaks down into hydrogen peroxide and sodium carbonate in water. The hydrogen peroxide releases active oxygen that lifts mold, mildew, and organic stains out of porous grout without harsh fumes or toxic residue.

Tips

• Safe for colored and tinted grout, unlike chlorine bleach which can strip dye
• Mix only what you need per session since the solution loses potency within a few hours
• Wear gloves to protect skin from prolonged contact with the alkaline solution
• Less likely than chlorine bleach to corrode metal fixtures or damage colored tile glazes