You can clean mold from your grout using household bleach and a spritz bottle. Fill the bottle and spray it on the grout, allowing it to sit for a few minutes. You may need to reapply depending on how moldy the grout is. While you can usually clean moldy grout, you may need to replace it if the mold is significant. In addition, worn-out shower seals increase mold growth, so ensure you inspect your shower seals for cracks or openings.