Don’t in a million years thing DH will actually go for this... we’re not talking about a small area and they’re white tiles with currently white grout. But I’d like to change to a dark grey grout and while expecting it to be a terrible idea, has anyone done it without losing mind, marriage or tile colour? I’ve seen things like this www.tradetiler.com/consumables/grout-colorant/universeal-grout-rescue-colour-seal-237ml-dark-grey.html