Spring pH changes

[ncpool]

Has anyone in the South seen their pH levels drop substantially (7.5 to 7.0 in a couple days) around this time of year? I have seen a lot of pollen floating on the top of the pool, and am curious if that has anything to do with it. PH hasn't been an issue in my pool so far, so i was surprised to see this.

Any sanity checks appreciated.

 

[iPhone]

Has anyone in the South seen their pH levels drop substantially (7.5 to 7.0 in a couple days) around this time of year? I have seen a lot of pollen floating on the top of the pool, and am curious if that has anything to do with it. PH hasn't been an issue in my pool so far, so i was surprised to see this.

Any sanity checks appreciated.

Seems like an extreme change. Where is your TA? If your TA is below 50, pH will start to bounce.

First I would retest with a sample from 18 inches down in the deep end. Make sure the test sample is right on the meniscus line and the bottle is completely vertical as you count the drops (and count accurately). One can always make sure of the exact color by adding one drop at a time of Base Demand to low pH to see how many drops it takes to get a color change to the next color on the chart (the opposite for high pH add acid demand).

How much of the rain did you get? Rain water has a pH of about 5, acid rain about 4. Remember that the pH scale is logarithmic. The difference between 7.4 and 7.0 is 400 percent not 4/10s.

 

[257WbyMag]

Just to make sure, are you drawing your water sample with the pool pump running? That water needs to mix well before a representative sample can be obtained.

 

[Prav]

Is it just because the water is warmer so the pH is just dropping naturally? I thought that was one of the reasons why during the winter (with colder water) the pH would be a bit higher than normal (and why it was OK not to add MA as long as it stayed in the high 7s).

 

[ncpool]

Thanks for the feedback folks. I have no idea what caused the sudden pH drop, but i added four lbs of soda ash, and two lbs of baking soda yesterday. pH looks good again at 7.6, though my TA is a bit high now at 110 (from 80). If i had it to do over, i would have just added the soda ash to up the pH, and waited on the baking soda once the pH got back to normal.

Thanks again.