Plaster (gunite) turning yellow

[bostonpool]

Hi folks.

Today is pool closing day. Overall my old (1978) pool has been in great shape this season. My chlorine got a bit high for a few weeks with my new SWG. But overall seemed fine.

Today, while the pool was draining down during closing, I noticed that my plaster / gunite seems to be very yellow this year. Not just in a few spots. The entire thing.

Does anyone have any idea what causes this? It looks fine when filled with water but I’m worried it’s a sign of a different issue.

My pool guy said “iron causes it”. Except I barely had to put the hose in my pool this year.

Thanks!

 

[ajw22]

Rub some areas with a paste of Vitamin C in a sock and see if it changes color. If it does your Pool Guy is correct and it is iron staining.

 

[bostonpool]

Rub some areas with a paste of Vitamin C in a sock and see if it changes color. If it does your Pool Guy is correct and it is iron staining.

Thanks. OK assuming it is, what can I do about it. It's all over every square inch.

 

[ajw22]

Thanks. OK assuming it is, what can I do about it. It's all over every square inch.

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