I am trying to choose a color of Diamond Brite. I have gone out to see two pools. One was white with blue quartz (I think it was the Diamond Brite "Blue" color). It looked perfect, very smooth and even. I viewed a darkish gray/blue mix Diamond Brite pool and the finish was rather streaky or mottled. Is this normal? Or does it mean the installer did a poor job? The mottled pool was only plastered a couple of weeks ago, wheras the light colored pool was plastered 6 months ago, if it matters. Does the streaking go away?