OXIDATION and Fiberglass pool

[GrkGod2020]

Hi there.....

Long time reader, first time asking a question or asking you the "Penny for your thought" question....

I have a fiberglass pool, (7 years now) and have been researching why my pool goes "White" when drained... well I believe I have finally found out my answer (Thanks to another member on here) Oxidation... I just recently started to use the Poolmath app and its awesome...tells me alot about what I was doing wrong... like CH levels being in the teens all the time, and not knowing what effect this has... now I do...

My question is simple... I heard that if I lower the PH level of my pool way down, that the "White" oxidation would be removed... I wanted to know if this is a good thing to try, and if I add muriatic acid to the pool, what is the dilution of it? 15200 Gallons.. If i do this, how to I raise the PH back up ? Pool pics attached...

PS.. I know the wall pic is calcium buildup, and I have removed that with muriatic acid... Just want to show the white aspect of the oxidation.

Humbly yours, Peter

 

[ChristenQ]

My understanding is that lowering the PH in order to get a slightly negative CSI would help remove scale, but not oxidation which is the breakdown of the gel coat and lowering the PH would not help in that case. Based on your pics I would venture to say that at least those white drips originating from the the tile area are calcium build-up and you could use some diluted acid to work on those. The chalkiness on the steps, I'm not so sure. It looks like mine, and it's so frustrating to think it may be the gel coat breaking down. I'm going to ask our manufacturer to come take a look at ours. You could test some diluted acid on it and see if it bubbles which would indicate scale. Just curious, do you use a Salt Water Generator? If your interested, put your specs in your signature and share you Pool Math data, maybe all of us on here struggling with this could find a common denominator.

 

[Texas Splash]

My question is simple... I heard that if I lower the PH level of my pool way down, that the "White" oxidation would be removed... I wanted to know if this is a good thing to try,

Welcome to TFP! Unfortunately, I don't think lowering the pH will help your issue. What you are referring to is almost like a "zero alkalinity treatment" which you can search here on the forum. Very difficult and risky to do, and I don't think that will help. I poured straight acid on my exposed chalky step and it did nothing. No fizzle means it's not calcium scale, so the low pH method should have no bearing. Christen made some good points. I think you have two issues happening. You what appears to be scale seeping-out from under the waterline tile. That might be treated with muriatic acid via a spray bottle and perhaps a 3:1 ration (water to acid) and brush. Maybe even some fine 600 to 1000 grit wet/dry (black) sandpaper. Always test an area first though. But for the chalkiness below the waterline, like some of us, it seems to be an oxidation process that can only be revered by re-doing the gelcoat.

Thanks for posting and sharing your photos. Feel free to discuss more if you like or have more questions. We can relate.

 

[GrandizerGo]

Hi Peter,
I'm from Brampton as well. When did you first start noticing the oxidization?

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