Very white grout in one pass: the method that “dissolves” dirt and removes it

4. In extreme cases, water and bleach
If the natural alternatives listed above do not give satisfactory results, there is only one way out: use bleach.

Wear gloves and pour 3 or 4 tablespoons of bleach for every liter of water. Use the solution to scrub between the joints with an old toothbrush and, after about ten minutes, wipe with a clean cloth.

Keeping your floor spotlessly clean and removing dirt between the joints is easier than you might think: immediately apply the tips described above to restore the floor to its original appearance.