I'm a fairly new pool owner that I inherited from the previous homeowner and I've used this forum almost exclusively to learn as much as I can.
There's a weird dark purplish discoloration on the pool walls and floor that I don't believe were there when we moved in 3 months ago. I rubbed a chlorine puck on it and there was no change. I used a putty knife to scrape some of it off and it was sandy and purple-ish in color. Prior to learning about CYA we used chlorine pucks and powdered shock only to have our CYA levels and hardness off the charts (CYA 200+ according to a test strip). We have a chemical test kit also but it doesn't test for CYA. We have a pool company coming out to look at it this week but I figured I'd see if any of the knowledgeable people here can help identify the discoloration. My guess is it's some sort of mineral deposit? Here are some pictures if that helps any.
There's a weird dark purplish discoloration on the pool walls and floor that I don't believe were there when we moved in 3 months ago. I rubbed a chlorine puck on it and there was no change. I used a putty knife to scrape some of it off and it was sandy and purple-ish in color. Prior to learning about CYA we used chlorine pucks and powdered shock only to have our CYA levels and hardness off the charts (CYA 200+ according to a test strip). We have a chemical test kit also but it doesn't test for CYA. We have a pool company coming out to look at it this week but I figured I'd see if any of the knowledgeable people here can help identify the discoloration. My guess is it's some sort of mineral deposit? Here are some pictures if that helps any.