Where do you get them from Gisella??
There are more, but the link below is a good place to start. I know it says grout, but it is suitable for all cement based products and a very well liked brand amongst mosaic artist.
A guide to the Dyegrout colors
If you google cement or mortar colourant you come across various sites that deal with or mention liquid colourant, added after the water, or the powder colourant option, added before. Adding colourant when dry is a lot easier to check for uniformity I would guess, (I have used powder, but never liquid, though I have used acrylic paint successfully, but dealing with such large amounts all at once I suppose it would be personal preference?
Black is a common choice though, so should be easy to get. 50 gr of powder dye is enough for 2.5kg addy or grout mix. Hope this helps?
I would LOVE a swimming pool, I really really would....one of those endless pools even, where you swim and swim against stream, a bit like a hamster in a wheel, but yes, would love it... sorry I digress.. :lol: