I am freaking out on this one...is this algae or something else? The pool was filled on Friday the 21st and I have been monitoring the cc and ph closely and the PB has a pool guy coming to help with start up and will be visiting my house every Thursday for about 2 months to help me get going. But on Saturday afternoon, I noticed these small black marks on the gray plaster...is it staining or algae or ????? I have been brushing the entire pool three to 5 times a day and the pump has been on almost non stop since pool was filled.
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