What could cause a "sudden" sharp increase in Calcium Hardness?

[hawkmoon7]

The Calcium Hardness in my nearly 3 year old plaster pool was always steadily maintained in the 350 to 400 range. So much so, that I haven't checked it in the last 3 months. That is, until it started to get a bit cloudy and I ran a complete chemical check using the TFP test kit. It is now 750! I know I have few options on lowering it and am considering either RO or draining. (I am also considering a stain control chemical and maybe a flocculant to remove some calcium to see what they can do, but I doubt it'll make a dent in lowering it).

But before I do anything, can anyone tell me what would have caused this sudden increase? I don't want to incur the burden of remediating this without knowing if it'll happen again because of something I'm overlooking.

Thank you.

 

[mknauss]

The calcium was added, or leached from your plaster.

Likely is high CH fill water and more added water than normal (less rainfall). Or you have been adding cal hypo.

 

[Bperry]

The Calcium Hardness in my nearly 3 year old plaster pool was always steadily maintained in the 350 to 400 range. So much so, that I haven't checked it in the last 3 months. That is, until it started to get a bit cloudy and I ran a complete chemical check using the TFP test kit. It is now 750! I know I have few options on lowering it and am considering either RO or draining. (I am also considering a stain control chemical and maybe a flocculant to remove some calcium to see what they can do, but I doubt it'll make a dent in lowering it).

But before I do anything, can anyone tell me what would have caused this sudden increase? I don't want to incur the burden of remediating this without knowing if it'll happen again because of something I'm overlooking.

Thank you.

Please don’t use floc, that doesn’t do anything for cloudy water like that. Stain control won’t do anything for cloudy water either. What are all your latest test results? That’ll likely provide a clue. A CH of 750 is high but isn’t that bad.

 

[hawkmoon7]

I've added a total of 5 gallons of cal hyp over the last few months, but that's it. I have also added a few inches of high-ish hard water. The rest must be from plaster I guess. So at this point, what's the solution? If I drain, I'm looking at like 50% of the pool and risk of the shell popping (it's rainy season here in FL). Should I just pay for RO treatment?

 

[duraleigh]

Regardless of the cause, you can take steps to manage it pretty easily. Please no type of additive like floc. R/0 is expensive, even if you can find someone in FL to do it.

Before we go further, what is the TA of your fill water?

Can you post a complete set of test results from one of the kits we suggest?

 

[JamesW]

I've added a total of 5 gallons of cal hyp over the last few months, but that's it.

Gallons of cal hypo?