Stains.... causes and anyway to remove?

nemeth8

Well-known member
Aug 27, 2018
98
Plano
Good morning,

Anyone help me out in figuring out these pool stains, and how to prevent/remove them? This is my first summer with the pool and as far as I can remember these stains have been here the entire time. My chemistry is good.... although earlier I realized that my CH was very low (100)... but it is up to 300 now.

Thanks in advance.
 

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