Yellow stains

[Zamsaf]

Hello all I have yellow stains on my plaster, but only near the return jets and in the exact direction the water comes out from them. Any idea what this is and how to treat/prevent it?

 

[mknauss]

Hello all I have yellow stains on my plaster, but only near the return jets and in the exact direction the water comes out from them. Any idea what this is and how to treat/prevent it?

Can you show us a picture?

Water chemistry test results also help.

Does your fill water have iron in it?

 

[Zamsaf]

I am attaching pictures of some of the jets. There are clear white areas where the jets don’t push water and darker yellow areas where they do. FC is 4 CYA 80 and PH is about 7.

I’m not sure about iron, I never tested it for iron.

 

[mknauss]

Get a handful of vitamin c tablets Put them in a thin sock and crush them up a bit. Hold the sock with the tablets against an area of staining. See what happens.

 

[Zamsaf]

Thanks I’ll try it

 

[Zamsaf]

I scrubbed the plaster with vitamin c and it went away. Is there something I can use to remove it faster? The spots are large and spread out throughout the pool, so doing it by hand is going to be very tedious.

 

[Zamsaf]

Bumping this

 

[mknauss]

Is there something I can use to remove it faster?

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