pH keeps creeping up

[mariner09]

I've also been experiencing pH creep. Over the last week, it's been hovering up around 7.8 - 8.0. To try something, I bought a bottle of pH down at Wal-Mart. I added about 24oz and got it down to 7.6. A few days later it was back up. Just finished the bottle this morning, 3 lbs of pH down in less than a week???

My TA is around 160.

I guess my bigger question is, is it OK to keep the pH up around 7.8?

We have had some big storms last week and more wind this week than usual, nice cold front came through in the middle of the week.

Come to think of it, one of my jets is pointed towards the surface and I have seen bubbles, maybe I need to lube the O-ring on the pump and re-prime..

[Amir]

Richard,
I can not access the link to the charts. Did you move them?
Thanks
Amir

[chem geek]

mariner09,

Yes, you can keep your pH at 7.8. The only downsides are a slight possibility of being more drying or stinging on the eyes since it's further away from the 7.5 that is around the pH of tears, but even that pH varies by person so I think you'll be fine. The other thing is that chlorine is a little less effective at that pH, but not by as much as the "traditional" industry graphs say because CYA helps to buffer disinfecting chlorine concentration. It's only around 10% less effective, so just bump your FC target up a bit to compensate.

You can lower your TA to around 80 to see if that helps. Then use 7.7 or so as your pH target after you've lowered your TA and I think you'll find a huge drop in the amount of acid you need and some drop in the rate of pH rise.

Amir,

No, I didn't move any of the charts and the link works for me right now and I don't have it protected in any way (i.e. it's visible throughout the world). Do you get an error message like it's a broken link? Does anyone else see that problem? Here are some links to various charts and graphs:

Free Chlorine Chart
Disinfecting Chlorine Chart
Outgassing CO2 Chart
Rate of pH Rise Chart
Chlorine Half-Life Graph (will be changed in future)
Disinfecting Chlorine Graph

Richard

[Amir]

Richard,
your links don't work! Would you please repost the links.
Regards

Amir

[fcfrey]

Richard / Amir

I just tried all of the links --- They work just fine. The first 4 are statistical charts not graphical but if you are skilled in Excel you could convert them if you wanted to. The last 2 links are logrithmic graphs.

All these should be Printed, Framed and kept where you can refer to them regularly. They are EXTRE E E E E MLY useful.

Quick related question for Richard, does aeration reduce pH along with TA?

Frank

[Amir]

Frank,
You are right! they work in internet Explorer but not in Firefox! I am not a big fan of microsfot so Firefox is what I used first and tried IE after your post.
Regards

Amir

[chem geek]

Amir,

I use Firefox on the Mac and the links work fine so this must be something specifically wrong with Firefox on a PC -- very strange.

Frank,

Aeration only causes the pH to rise by the outgassing of carbon dioxide. It does not change the TA. When you add acid, then that lowers both pH and TA so the combination of the two is a net result of lowering TA. Carl explains this here and I have a chart about this here.

Richard