PH Keeps Dropping

[rilesworld]

Richard,

I would be happy to try an figure this out because it has been puzzling me as well.

Answers:

1) There was a solid pool cover put on this winter by the previous owners. I took it off in December and there has been no cover on it since. I do not own a solar cover.

2) I don't really have any sources of aeration. Just two returns, although I have been getting some air in my system that I haven't tracked down yet as I get small bubbles every so often that come out my returns. I think it is from a bad seal on the pump basket.

3) No other chemicals are added except bleach and borax.

4) I do have quite a bit of leaves that have been falling in the pool. Had that under control until we got a late freeze in April and all the leaves of the surrounding trees died. It was like fall all over again . I also get a fair amount of pollen. Another thing I have been finding is that the pool is dirty with silt a day or two after vacuuming. I assume it is from the silt just getting stirred up when I vacuum and then settling back out. I have been meaning to test to see if I am getting any blow by from my filter. Other than that I get a few worms and salamanders on occassion.

5) No runoff from nearby soil or other liquid is finding it's way in that I know about.

6) The pool gets quite a bit of direct sunshine through most of the day.


Hopefully I answered all your questions. I will hold off on adding any baking soda to see if there is some other reason for the dropping Ph.

Thanks,

Riles

[chem geek]

Riles,

Try this. Take a large bucket of pool water and place it near the pool, but cover it with a cloth. See if the pH drops in the bucket as quickly as it does in the pool. If it doesn't, then perhaps the leaves or pollen or other junk getting into the pool is acidic. That's my best guess at this point. Perhaps someone else has an idea as well.

[EDIT] A better idea would be to have TWO buckets of pool water -- one without the leaves and pollen and the other with leaves and pollen. Measure the pH of each (they should be about the same), then cover them both so they don't get more stuff in them, then see if the pH changes differently in the two.

If the problem ends up being the leaves and pollen, then raising the TA would be a solution, but you may need to lower it again when the leaves and pollen stop dropping. I'll be surprised if the leaves and pollen are causing this, but I don't have any other answer for it.[END-EDIT]

Richard

[aylad]

Have you tested the pH of your fill water?

Janet

[rilesworld]

I have not tested our fill, but we have not put much fill water in the pool yet this year. I can run that just to find out though.

I have no idea what was used to chlorinate up until I took ownership in October of last year. Could that have any impact? Some sort of residual from an acidic-type chorinating left over? Seems highly unlikely, but I'm reaching.

What sort of normal drop in Ph should I expect? Let's assume there is no rain or chemicals (aside from bleach) being added? It seems like it should remain relatively constant if no acid is being added.

I'll keep you posted.

Riles