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Thread: PH & Acidity of Water on metal parts in pool water

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    Catanzaro's Avatar
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    PH & Acidity of Water on metal parts in pool water

    I figured a new thread would be more in line. Can PH drift (upwards) that stays in the 8.0-8.2 range for a period of possibly 2 weeks, cause any type of rust transfer on screw heads? I know that we have been attacking this subject for a while. I spoke to the warranty dept. about the screw heads, etc. They claim that water chemistry, the PH is what caused it. He may have claimed that the PH of the water "stripped the galvanized screws", which sounds to me like they were coated and not of a quality stainless steel. I do not recall if he used the word "Stainless" in the conversation.

    If this is the case, then inferior screws would react pretty quickly to high PH. I am keeping the PH at the 7.5 level and adding 10 oz. of muriatic acid about every 4-5 days. Now that the pump is running less, the additions are less frequent. At one point, it may have drifted up for a short period of time. Thank you.
    14,700 gallons IG Pool Vinyl Liner - Octal Circulation System
    Hayward Pro-Series 350 LB. Sand Filter Model # S270T - 2" Plumping
    Hayward CL2002 Chlorinator - Hayward Super Pump 2 HP Model # k48m2n111
    Hayward AQR9 SWG 25K Salt Cell & TF-100 Test Kit + Speed Stir
    Gulfstream HE125RA - 117K BTU Heat Pump - Date of Build is 11-2013

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    Re: PH & Acidity of Water on metal parts in pool water

    A galvanized screw, once the anodic coating is consumed, will invariably rust. That the warranty department knew of zinc plated screws implies that the construction is of inferior materials and is known.

    You probably just want to cut your losses and replace all of the poor quality screws with a 316 stainless.

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    Re: PH & Acidity of Water on metal parts in pool water

    Starting a new thread is seldom helpful because you refer back to another thread and almost no one will take the time to go back and see what you are talking about, Even if the subject changes, you are better off staying within one thread.

    Metal is most susceptible to LOW pH, not high. Certainly galvanized screws will corrode much quicker than stainless. I would be a bit reluctant to call them inferior but they are not as good as stainless.
    Dave S.
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    Re: PH & Acidity of Water on metal parts in pool water

    It really was not a new thread (Per Se), old message was about muriatic acid interacting with any other chemicals in pool water. This is mainly due to PH drifts and that is what they are blaming the issue on. Clearly, we all know it is inferior screws. Hayward sent me new screws and it appears they have a nice shiny coating and are definitely better stainless. Next time, I will piggy back on old threads, if applicable, and please accept my apology for starting a new thread..

    PH closed at 7.6 in September and opened at 7.2 in April. Drifted slightly above 8.0 for a short brief few weeks, but I still believe bad screws (twice). As I mentioned previously, I do not know if Stainless Steel screws are still coated (which I assume they are), or if they were "galvanized". Only time will tell with the new screws and new white niche face plate.
    14,700 gallons IG Pool Vinyl Liner - Octal Circulation System
    Hayward Pro-Series 350 LB. Sand Filter Model # S270T - 2" Plumping
    Hayward CL2002 Chlorinator - Hayward Super Pump 2 HP Model # k48m2n111
    Hayward AQR9 SWG 25K Salt Cell & TF-100 Test Kit + Speed Stir
    Gulfstream HE125RA - 117K BTU Heat Pump - Date of Build is 11-2013

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    Re: PH & Acidity of Water on metal parts in pool water

    The shiny coating is evidence that they may have been passivated.... or coated with a light film of oxide to protect them.

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