PH Question

[TarheelFan]

This is my first season running my 15x30 oval above ground vinyl pool after getting it installed very late in the season last year. I opened it and had a minor algae breakout, but have been able to get that under control and my water has been crystal clear for a couple of weeks now. However, I am concerned about my pH. I have ordered the Taylor's test kit (should arrive Monday) but have been using test strips for the past week. Even with two different brands of strips, I can not tell if my pH is 6.8 or 7.8.

I know 6.8 is bad for my pool (including my newly installed heater), but I do not want to just dump chemicals and end up with a sky high pH. Thus, my question is this....can I afford to wait until Monday (or Tuesday) to deal with my pH or should I go to Walmart and get their cheap drop test and deal with the pH over the weekend?

 

[JasonLion]

Welcome to TFP!

How high is your FC level? When FC is too high (usually 18+, but possibly at lower FC levels with some test strips) the PH indicator will turn a color that isn't on the color chart and which is confusingly similar to both 6.8 and 8ish.

 

[TarheelFan]

Thanks for getting back to me (and for the welcome). I have been reading this forum and the other one like mad trying to learn what my pool guy neglected to tell me.

My test strips show the FC at between 3 - 6. My CYA is fairly low, as I have not added any, but I have used a dozen or so pucks since filling the pool, so I would guess my CYA is less than 40, but higher than 10.

I went ahead and went to Walmart and bought their $8 test kit to try to get a better pH reading. It clearly showed the pH as high rather than low (would estimate 7.8 - 8.0), which makes me less worried about damaging my heater. I have not added Calcium specifically, but have been using Cal Hypo to shock. Even so, I have only added about 5 -6 lbs. of cal hypo since the pool was filled, so my Calcium is still pretty low. If I have read and understood correctly, the primary concern with high pH in a vinyl pool is scaling from minerals like calcium in the water....is that correct? Are there any other major concerns for high pH in a single family pool?

 

[JasonLion]

High PH can lead to calcium scaling and metal stains, and if it gets really high it can interfere with chlorine working. None of those seem likely given your levels. The normal recommended PH is between 7.5 and 7.8, so really you are just fine.

 

[TarheelFan]

Awesome! Thanks again for the quick responses! Time to take a dip and relax then.