Our shower floor is marble basketweave (crema marfil with emperador). It has been installed and grouted, we now need to seal it before the wall tile goes up. The grout color is very similar to the color of the tile. How do we ensure we got all grout off the tile? I know it sounds like a funny question, but I can't really tell by looking at it. There isn't any more of the obvious grout haze it initially had and feels clean. We washed it with just plain water, changing the water frequently, because the special cleaner didn't pass the test. Is it enough? The sealer is Aqua Mix