I may remodel a bath which currently has 70's green tile and white grout, and cheapo vinyl flooring. I typically use Tilex with bleach to kill mildew on the grout and around the edges of the flooring. Can bleach be used on the darker type of textured tiles and grout that is typically used in modern bath flooring? I was thinking of using similar dark tiles+grout on the walls, but maybe the tiles there would be glazed so bleach might not hurt them, but not sure about the dark colored grout.