Tackling grimy grout not only revitalizes the look of your tiles but also brightens your entire space, making it feel cleaner ...

Use the rinsed toothbrush or a grout brush to scrub the grout lines by applying a bit of water to the brush. Focus on areas with visible stains. Use the cloth to wipe any excess solution ...

Then I squirted Zep directly onto all the grout lines, no brush needed at that point. Zep recommends application to grout lines only, so I tried my best not to get it on the rest of the tile.

It's conveniently water-resistant, with a small brush head designed to fit into tight corners and small spaces — think grout lines, faucets, window edges, tire crevices. I also knew my own hands ...