Black dots and white areas - I am lost as what is happening

Nov 2, 2015
12
Mobile,AL
Not sure what has happened. Just bought the house 2 months ago with a pool. It did not have the white areas or black dots before. At least none that I noticed. Water was not as clear as it is now. Seems like the more I do to care for the pool, the worse it is. The black dots will not scrape or brush off, nor will the white areas. Its like its part of the plaster. Black dots, which are really small seem to be getting worse. See pictures attached. Water is crystal clear and here are the lates test done with the K2006 kit. Water temp is 62 today.

FC - 3.8
CC - 0.0
Ph - 7.6
TA - 75
CYA - 55
CH - 290
Salt - 3300
 

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The second picture shows black dots around the white area. It looks like someone has taken a black marker and made dots all over the pool. They will not scrape off at all. There not slimey or rough to the touch. I now started to get come brown staining in some areas. Any thoughts please. Water is clear. Plaster is 5 years old. Could it be time to replaster already? And how much does that cost. 16x32 peanut shaped pool. 3.5ft shallow end 6 ft deep end.

FC - 3.8
CC - 0.0
Ph - 7.4
TA - 75
CYA - 55
CH - 290
Salt - 3300
 
Have you ruled out anything organic with the OCLT?

If your CYA is 55 (I would round up to 60 for safe measure), your minimum FC should be 5 instead of 3.8 and your target should be 7.

Perhaps you could bring the chlorine up to shock level, brush the walls and floor well, then perform the overnight loss test just to be sure.
 
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