You should make a decent gray with black colorant.

The second question..it depends on how deep you want your color. Usually I end up with mostly paint and wet it enough so that it spreads easily, but if you want a lessi ntense color ,you can add more water

Thanks, Shirty. I didn't even know it was paint or water based. It looked like it might be a powder. Good info, and I appreciate it.

I've done a color wash over grout...just using my craft paints. And have also added it to the grout. Either works for me.

I've used it too, Calamity, but have been told it will fade outside and that it deteriorates the grout over time. Have you found that?

Does anyone know if I can use black to make a suitable gray for grouting if I'm mixing it with white thinset?

I have used acrylic paints in grout with success and I have used black to make a grey, sparingly.

are you using a dry colorant daisy? If thats the case, then yes like Shrty said, it can be added to any white concretious product like grout, thinset or mortar and you can make various shades of grey. It will be lighter when dry compared to when you mix it.

My first BB grout was colored with acrylic paint added to the mix and it did fail within a year. I cannot say it was due to the paint but I have no explanations for it.

Hmmm, I'll have to see if it was you that responded to me on the other forum or whether someone else had a problem with groutafter adding acrylic paint. I'll let you know. Maybe that would answer your question about your fail.

I am using liquid colorant and I'd use just a touch. I just wondered if people do that rather than also buying gray grout. This black is so intense it'll last forever even if I also use it for gray.

Yeah then I think you should be just fine. With using paint, it takes a whole lot to get the colors deep and there's always been concern with too much it might affect the chemistry of concrete curing.

FYI, I only ever buy white and black grouts and make all my own colors from those. Adding powdered colorant to black grout can make some great saturated tones and gets you out of the pastel ranges.

for instance, here is plum added to black

and this has green added to black

Nice! Thanks for those pictures of the grout using blacks and colors. I wouldn't have thought of that, and I love the result. Do you use powdered colorants? Do you ever still use acrylics?

Yes I try to have all the colorants on hand and will ocassionally add a bit of acrylics to adjust colors. Like yellow paint with terra cotta colorants to get a better orange. Or red paint with brick red colorant to get a stronger looking red.

then I still like color washes too as in the case of my stairs which I grout in white to start with. Then used watered down paints over all the matching colors. lots of options to play around with and I only ever have 2 cartons of groutsitting on my shelf.

NT. "I only ever have 2 cartons of groutsitting on my shelf". Good point and reason for using powered colorants! Thanks!