pH keeps creeping up and can't keep chlorine level up

[ajw22]

Little change. 7.5 this morning.

Great. Now test your FC daily and add CL as necessary to keep it at 7.

Go swim!

 

[JoannaB]

Thank you! I still need to find a long term solution to obtaining 10% bleach without long drives in traffic. I went to the pool store today to replenish my re-agent supply and asked if they stock it. Of course not. He recommended Cal-Hypo, which I am still considering going back to just for convenience sake. Then he brought over this gadget called a Nature2 cartidge that uses silver nitrate and 'ions' to reduce the amount of chlorine needed. I was skeptical and told him I'd do a little research. I see that it's not recommended by anyone on this site. I figured as much. Thanks again for all the help!

 

[ajw22]

With CH of 190 you can get away with cal-hypo for around 5 months. That should cover your pool season.

With cal-hypo for every 2ppm app of CL you will get 1.4ppm of CH.

Monitor your CH month to month and see what it is when you close your pool. Then see what it is next year when you open after draining and dilution. You need to see if it is a long term solution. If not a SWG is the way to go.

Watch your CSI withPoolMath and keep it between 0 & -0.3

 

[JoannaB]

I downloaded the PoolMath app and will be using it. Here in Portland, I don't close like you do in the NE. We don't hard freeze. So in Oct I just put in a ton of bleach and turn off everything. Worked well this year. Pool was only slightly cloudy when I powered up in late May. The frequent chlorine adds is just something I was unaccustomed to before. I'm getting it now. What is CSI and how do I test for that?

 

[justinc]

What is CSI and how do I test for that?

Calcium Saturation Index (CSI)

How is CSI calculated? Very simple – use our PoolMath tool. To ensure long plaster life and save money, click here to learn more.

www.troublefreepool.com

"How is CSI calculated? Very simple – by using the PoolMath tool. Since CSI is primarily calculated by combining pH, TA, CH, and water temperate (among other items), simply enter your test results in PoolMath and refer to the CSI row. The tool will tell you if your water is balanced or if there is a potential for scale or erosion. "

 

[ajw22]

Your risk of putting your pool to sleep with a CH of 500+ is that your pH will rise over the winter and you will develop scale on the plaster. As your CH rises you need to keep your pH lower in the 7s to prevent scaling. The CSI is a measure of the likelihood of the water to scale if overly positive or etch the plaster if overly negative.

So use cal-hypo with caution as it can have long term side effects. Scale is not easy to get off plaster.