I found this picture on fb of a pool and inquired about the unique water color. They said PB used a formula of 40% black and 60% French grey. What does this mean? Formula for black is 11 bags black and 1 bag white with black liquid pigment. Formula for frech grey is 11 bags white and 1 bag black with French grey liquid pigment. I wonder how many bags of each did this PB use? Can you pool plaster experts help me figure this out? Getting plaster with stonescapes mini pebble in 1-2 weeks and I need to decide. Any suggested are much appreciated 
