Advice on cleaning dirty water line by white steps

[Janelle]

Hi there,

My pool has been clear all summer, no algae or obvious water issues. I am having an issue with the white steps into the pool though. They are beginning to yellow a bit. Also, at the water line, it looks dirty(grayish stains). Am wondering what this is from and looking for tips on how to clean and what to use. I've tried scrubbing, but it doesn't come clean.

Here are my #'s

fc 6
ca 197
ta 75
cya 45

Thanks!

 

[northrn]

I've read here about people using Magic Eraser for the scum lines that sometimes form.