Plaster Stains

[edima302]

Hi I have a gunite pool with Diamond Brite finish (French Grey) which is now 7 years old and all of a sudden I’m noticing brownish looking spots on my steps (not on actual pool bottom) that when I brush it appears to mostly come off. At first I thought it was sand from the paver patio that washed on my steps. I’ve attached some pics I would love to know what it is and if there is anything I can do to get is completely off. Thank you !

 

[ajw22]

Looks like copper or iron stains. I suspect copper.

Make a paste of Vitamin C and put it in a sock and rub it on the stain. If it lifts it is iron.

Stain ID Kit | Jacks Magic

jacksmagic.com

Copper in Pool Water - Further Reading

www.troublefreepool.com

 

[edima302]

Do you what could be causing it if it’s iron or copper ?

 

[ajw22]

Do you what could be causing it if it’s iron or copper ?

Using chemicals with copper in it.

Fill water with iron in it.