I know you all said to not worry about other levels until the FC goes below 10, but do you still say that given how long it will be? I‘m used to adding acid several times a week. It’s really ok to have a high ph this long?
Yellow algae, need help
- Thread starter smithkl
- Start date
Any long term affects are just that, and take as such. You'll be fine from the short term. (Seemingly being exponentially longer sitting there waiting for something to do).
The Ph meters aren't affected by the higher FC but the cheap ones aren't very reliable and any of then are finicky needing calibration at times and to be stored a certain way. You can pick one up or just pour a beverage and enjoy the break.
- Mar 5, 2020
- 3,196
- Pool Size
- 66000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Astral Viron V35
Should all be fine. If nothing bad happened by now (like water turning green due to metals), then it will not happen in the remaining time where pH might be elevated. And high CSI is more of a long term problem.
If it makes you too nervous, you can make a 50:50 dilution of a pool water sample with distilled water. Not tap water or bottled drinking water. Distilled water has very low Alkalinity, but your pool water has Alkalinity and will therefore buffer pH changes introduced by the distilled water. That's by the way also the explanation (apart from the small volume effect) why rain water has little direct effect on a pool's pH. The dilution will half the FC level, so if you started below 20, you'll now be below 10 and have no chlorine interference with the pH test anymore.
But keep in mind that there is a natural pH swing with FC going up and down. Adding chlorine raises pH, using chlorine reduces pH again to where it was before, the complete chlorination cycle is pH-neutral. While maintaining target FC levels, the pH-swings by adding and using chlorine are pretty much negligible. Any net pH drift comes from CO2 outgassing driven by high TA. When adding a lot of chlorine to reach SLAM FC, or even MA -FC, pH will get a noticeable bump. But this will come down again once FC is back down, so you don't want to over-correct. That's why TFP asks to lower pH down to 7.2 before starting a SLAM, and then don't worry about pH until after the SLAM.
If it makes you too nervous, you can make a 50:50 dilution of a pool water sample with distilled water. Not tap water or bottled drinking water. Distilled water has very low Alkalinity, but your pool water has Alkalinity and will therefore buffer pH changes introduced by the distilled water. That's by the way also the explanation (apart from the small volume effect) why rain water has little direct effect on a pool's pH. The dilution will half the FC level, so if you started below 20, you'll now be below 10 and have no chlorine interference with the pH test anymore.
But keep in mind that there is a natural pH swing with FC going up and down. Adding chlorine raises pH, using chlorine reduces pH again to where it was before, the complete chlorination cycle is pH-neutral. While maintaining target FC levels, the pH-swings by adding and using chlorine are pretty much negligible. Any net pH drift comes from CO2 outgassing driven by high TA. When adding a lot of chlorine to reach SLAM FC, or even MA -FC, pH will get a noticeable bump. But this will come down again once FC is back down, so you don't want to over-correct. That's why TFP asks to lower pH down to 7.2 before starting a SLAM, and then don't worry about pH until after the SLAM.