I had 6" red quarry tile with black grout installed in my floor entryway 14 years ago. For a while, I mistakenly used a floor cleaning product that had wax in it. The black grout is now mostly grey and the only time it actually looks black is when it is wet. I have tried a wax stripper but it hasn't helped. The tile is in excellent condition but the color of the grout is awful looking! If I have to completely remove the old grout, what color would work best so it doesn't always look dirty and how do I regrout the tile?

Color is very subjective and it boils down to what you like. I'd recommend a 2 part epoxy grout to prevent a repeat of your problem. Once the epoxy sets it is stain proof.

I had 6" red quarry tile with black grout installed in my floor entryway 14 years ago. For a while, I mistakenly used a floor cleaning product that had wax in it. The black grout is now mostly grey and the only time it actually looks black is when it is wet. I have tried a wax stripper but it hasn't helped. The tile is in excellent condition but the color of the grout is awful looking! If I have to completely remove the old grout, what color would work best so it doesn't always look dirty and how do I regrout the tile?
I got one of them quarry tile fireplace hearths with the black grout. My folks do rental houses and were in town and noticed the grout was lightenng up so just took black shoe polish wax and put that over the grout lines. I was skeptical but amazed at how well it came out.
You might try this as you don't have anything to lose but a lot to gain.
Best of luck.
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