How much water do I mix with Mapei unsanded grout?
https://www.youtube.com/watch?v=hfgXQJiwJUA
Can you add water to Mapei grout Maximizer?
If using a grout additive, such as MAPEI's UltraCare® Grout Maximizer, keep the correct ratios of liquid additive to grout powder, do not add water, and adhere to the mixing and resting times. Use a drill rather than mixing by hand. Do not add more liquid additive or add water if the product begins to thicken.