I use Finazzle Grout Cleaner for Color Grout and Finazzle Soap Scum Remover. I learned about the products from this forum, and purchased from local True Value Hardware store. The contractor suggested Tilex Soap Scum Remover. I think either product would work. Snookums2, I wonder about the products used in the shower too. They are fancy designer line received as gift, not the plain ones we usually have. In our case,the color of the grout, its composition and hard water all contribute to the color variation. Raehelen, I sealed Guest and Master bathrooms floor with 511 Impregnator Sealer. The shower floor will be the next. DH said there is some degree of color variation in any grout work. It is true. He did not think shower looked bad even before I re-cleaned it. Guess it is the difference between regular people and the anal Garden Web type like me who examines every single detail so very closely. LOL!

I just broke my record for using Custom's Charcoal, a 17-bag job. Oooompah. Residential, not comercial. As the name implies, it's not a "black" black. It'll dry to charcoal, a "dark" dark gray, or a "light" black if you want to twist things that way. Aqua Mix colorants are excellent. There are a few ways to apply it, either just on the grout or with a technique that Bill described on another forum. I'm sure he'll pipe in with a link. You can be a bit sloppy in the initial application, but the big caution is to not let the colorant dry on the glazed tile surface. If a natural stone, then I'll be very very precise in applying the colorant just to the grout. I'm honestly not sure if the negative press about Custom is due to the product itself or that the product is carried in HD box stores and as such it's used more by the DIY crowd. Or used by "pros" that shop at the box stores. Who knows. I know a few DIYers that put supposed pros to shame. I did have one bad experience with Custom's grout many many years ago. They did have a bad lot, it seemed a bit off when I was mixing it, and the grout failed as it cured. They totally backed my claim and then some, no argument from them at all. That's one bad experience that was back in the mid-90s.

As mentioned by a few and above I'd go with a grout that matches your wall tile and one that is very light for the floor. I would probably do white on the floor even though you have the little gray squares within the floor tile. They don't need to be the same grout colors being wall/floor.

Needs to be a light color to match the tile, so I would match as close as possible. Tough to say a color as the tiles are a bit all over the place color wise plus the computer monitor changes the color as well.