Heather Vance from Indoor City explains how to clean grout.
Prevents Staining and Discoloration
Indoor City installs a high-performance, fast-setting polymer grout called Permacolor. Made to prevent staining and any type of discoloration, it has built-in Microban technology to prevent mold and mildew from soaking into the grout.
You can clean it with a grout cleaner product available at your local hardware store. Just spray it on and wipe it off.