Our plaster (quartzscape barbados blue) has various "splotchy" areas. Our company advised us to complete the heavy brushing period and see if the areas improve, but they have not. See pictures. They are in the shallow end of the pool. All of the pictures except one are of larger patches, each a couple feet across, which have been there basically since the beginning (June 22). Then one picture is of some small patches, these are only about the size of a quarter, they’re on the sunshelf, and we have only noticed more recently. What caused this, and can it be fixed, or should we just live with it? Our chlorine and pH levels have been spot on the whole time. Do we need a zero alkalinity treatment to fix it? We are new pool owners, never owned a pool before, so we are rookies about all of this. I am contacting the PB as well but wanted to hear other opinions... Thoughts?