I've tiled my own two bathrooms and my kitchen backsplash, so when my adult daughter's shower sprung a leak at her "new" (circa 1950) home, DH & I came to the rescue. Ripped out the whole tub surround (it gave up without a fight), fixed the plumbing, reinsulated, added backerboard, taped, mudded and commenced to tiling. Got complicated around the tub; being an old steel tub, it has about a 1" flange around the top edges as though it's supposed to bolt to something? We ran the backerboard down to within 1/4th" of that flange, did the tape /mud/dry time thing and then commenced to tiling. When I got to the grout, I must say, the grout was a tad drier than I'd liked for it to be, but I worked quickly and thought I'd done okay. We spaced the bottom row of tile to cover that backerboard/flange gap, which it did okay. Then I left my daughters to finish grouting the normal 1/4th gap around the edge of the tub. I would have used caulk, but since the gap varied some, the girls used the regular grout to finish off that bottom edge and the corners. Are you with me so far? It looked really nice. Now I notice a lot of little tiny cracks in the grout all over and I'm thinking I'll be okay to just smash in another coat of it. (She hasn't used any tile sealer, yet.) EXCEPT.........she called tonite to say the whole bottom row of that grout is soaking wet, coming out in big soggy clumps and some of the tile with it. My thoughts are that she didn't let the tile cure enough before going in and using it, so now we need to pull out all the soggy stuff and redo it from there. So, the questions are: did we handle the backerboard/tile/grout around that flange right? Or is there just enough movement in a steel tub to disallow a grout (vs caulk) to flex. If that makes any sense.......And the second question is: am I on the right track to fix it? How long does it REALLY take for tile to cure enough to take a shower? Please tell me I don't have to take down this whole job.....this is a single mother with a TEENAGE daughter who will just DIE if she doesn't get to shower. Thanks for reading this far............. mm

Yes, you can, and regardless of what the color is now, or what you want it to be, it can be done, and relatively easily. You said you've done some research and found the reference to Aquamix's colorants. They're the best there is. I have a link to where you can buy them on line, as well as a forum thread that gives explicit directions on using them. Here's the url to buy them on line: http://www.1877floorguy.com/grcopr.html And below is the link to the forum thread. Refer to reply #2: Here is a link that might be useful: Using Grout colorants

I don't know enough about your shower to provide positive guidance. Dark grout is usually a sign of water absorption and/or intrusion. It can sometimes show a dark grout around the perimeter of a floor, sometimes with moisture wicking up and darkening the grout in the lower walls. But that usually occurs after more than just a few showers. It can show as a dark ring around the drain. Sporadic dark spots on the floor could be due to slow draining "bird baths", or slight irregularities in what should be a nice continuous floor slope from wall to drain. Built-ins like benches can be hot spots if they were improperly detailed during construction. It's tough to say what your problem is. The typical first question is: Did they install the waterproof membrane in the shower floor on a sloped surface or was it installed directly on the flat subfloor? An overall photo of the shower might help.

I agree with his fix, although I'd be using siliconized latex caulk from the same company that made the grout. In fact, it shouldn't be "the fix". It should've been done that way in the first place. I would have him score out the rest of the grout in that joint around the shower and caulk the entire thing, because the rest of it WILL come out, sooner or later.