Utilizing harsh cleaners can often time damage your tile and grout and break down protective sealants. The best way to clean your grout yourself would be a mixture of baking soda, hydrogen peroxide, and dish soap, using this mix let it sit for about 10 minutes. Then using a brush scrub with some force to really dig deal and clean up any stuck in dirt and grime. We know this can be quite a tedious process to save you some time you can give us a call to take care of it for you! (410) 944-4677