Our design team suggest you use grout colour 08 Cement.
Kerakoll Fugabella Color Grout 08 Cement 3Kg – Baked Tiles
Recommended Grout Joints - We have assumed that your substrate has a perfectly flat and plumb surface, please check with your tiler.
For a traditional look - 5mm grout joint. Based on this joint size, 1 bag of grout would cover 13m².
For a contemporary look - 3mm grout joint. Based on this joint size, 1 bag of grout would cover 21m².