Recurring Metal Staining


Silver Supporter
May 15, 2021
Murrieta, Ca
Metal Staining is returning mid August, 3-4 months after the May AA treatment. I knew this would happen. I’m going to have to accept that an annual AA treatment is necessary. Here is why:
Iron and other metals are found in gas and Diesel engine exhaust, as well as in road grit.
I live on a corner lot across from an elementary school. A ton of cars wait on the curb all along my street and right next to my pool for as much as an hour until school is dismissed. Metal staining accelerates in my pool when school starts in mid August as parents idle their gas and diesel engines for about an hour on my street-side yard and the prevailing breeze blows it over into my yard & pool. This calms down in cooler weather when idling for a/c is not necessary. Also the food supply trucks idle their Diesel engines for a good hour several times a week. The road grit kicked up by passing cars also accelerates when school is in session.
Just wanted to put this out there for those of you in similar situations.
I’m so glad this forum is here to help me take care of my pool!!!!!
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Mod Squad
LifeTime Supporter
Jan 17, 2012
Evans, Georgia
Marie- have you tested for which metals are causing you grief? Are you sure its lead, since gas nowadays is lead free? I imagine diesel isn't though?

The most expensive cure for this is an autocover..... a cheaper option might be a better fence? Higher??

Is the water getting discolored or just stains on the pool?

Maddie :flower:


Silver Supporter
May 15, 2021
Murrieta, Ca
Hi Maddie,
Thank you for your comments! My plaster is staining, likely it’s iron. Pool store test been showing 0.1 iron and iron is primary component of exhaust and road grit. Plus the vit. C test makes it obvious🥴.
Also, my pH keeps going from 7.5 to 7.9 in 3 days or less, so adding MA 2-3 times a week. When pH is high for a while it causes the metal to come out onto the plaster. So I’ve been trying to keep pH lower but it drifts up too fast.
FC 6
CYA 58
TA 70
FC does not drop fast at all, in fact it easily gets too high. I am not using pucks only SWG. Still trying to figure things out.