[drawlins27]

If all else fails, Home Depot has an acid based grout cleaner that is wonderful. I can't remember the name but it comes in a yellow bottle. When I bought my house, the previous owners had put down ceramic tile in the kitchen years ago but failed to seal it. The grout was suppose to be a light gray but was black instead because it had never been sealed! I tried eveything to clean it including soft scrub and bleach but it made no difference. I used this grout cleaner from Home Depot and a special wire brush for cleaning grout (also available there) and it made the grout look brand new. If too much of the grout has worn away, you may need to add some.