Keeping calcium in water!!

[MCF50]

We all know calcium deposits are a result of high pH. Many of you have advised to let saltwater pools rise up to 7.8 as that’s where they like settle. I add muriatic acid to keep it down around 7.4. For those of you that keep ph at 7.8 or 8.0, how do you prevent calcium build up?

 

[mas985]

It isn't just PH that is the problem, it is CSI that really matters but PH is a large component of CSI. So I try to target a CSI of around -0.3 which works pretty well for both the tile and SWG. But if I let it drift and get too high, I see the consequences pretty quickly.

If you want to maintain a high PH but a low CSI, then you will need to keep both TA and CH on the low end of the scale which is not always possible.

 

[MCF50]

Thanks. Yes. Higher ph and lower TA is a challenge. Keeping hardness down for me isn’t though. So maybe I should let CH get to around 250? I usually keep it around 400. And yes I get calcium buildup quick if I don’t keep ph under 7.6.

 

[mas985]

Lower CH, and then set PH such that CSI = -0.3. TA will then take care of itself. But if you have high TA fill water and need a lot of it, then you will need to constantly add acid. Consider an acid dosing system. That is what I do. I have both high TA and high CH fill water so not much I can do but keep PH low.

But I wouldn't think high TA fill water would be an issue for Houston.

 

[MCF50]

Thanks. I would like to do a dosing system. What do u use? I don’t want to mess with the Pentair one.

 

[mas985]

I have gone through several iterations of a DIY system. See signature. I have added a peristaltic pump for a bit more control.