Not an issue really, but wondering about pH increase...

[DiverGirl1972]

We just fully opened the pool and over the past couple of days, and I've been adding the chemicals needed to get ready to start up our SWG for the first time. I will say, my pump and filter have been running for the past month and I've been adding liquid chlorine a couple of times of week to keep the FC levels steady, but it was covered with both a safety cover and a tarp.

Before adding anything, my starting numbers were:

FC 6
CC .5
pH 7.2
TA 50
CH 50
CYA 20
Salt: 1000 (Taylor salt kit)

My plan was to add about 30 lbs of calcium chloride to get to CH 200, 400 lbs of salt for a target of 3200 ( I went lower than the 3600 goal, as I knew the calcium chloride would also increase my salt level) and 3 gallons of liquid conditioner for an initial target of 70.

Ended up dumping in 400 lbs of salt first (yeah, should have snuck up on it! lol) which was supposed to get me to 3200 and I added the 3 gallons of conditioner. After an hour or so of brushing and allowing everything to get mixed up, I retested salt, CYA and pH and got 3800, 60 and 7.5 respectively. Bummed the salt ended up higher than anticipated, as now I don't feel like I can't add the calcium, and I guess my CYA was only 10, as my re-test only got me to 60.

Curious as to what would account for the .3 increase in my pH after adding the salt and CYA? My pH naturally seems to stay pretty stable at 7.2. Our fill water is 7.0. I don't have any water features and the returns are not pointed at the surface.

Thanks!

 

[mknauss]

You do not need to add that much calcium anyway. If you are seeing foam, add another 50 ppm or so of CH. But your vinyl liner does not need any calcium and your heat pump is not like a regular pool heater in needing calcium.

Rise in pH == aeration or chemically are the only to ways to raise pH. So most like aeration.

 

[DiverGirl1972]

You do not need to add that much calcium anyway. If you are seeing foam, add another 50 ppm or so of CH. But your vinyl liner does not need any calcium and your heat pump is not like a regular pool heater in needing calcium.

Rise in pH == aeration or chemically are the only to ways to raise pH. So most like aeration.

That's what I figured, but when I brushed, I used long slow strokes and I've tried aerating MUCH more vigorously in the past in an attempt to increase pH with no results. Oh well, I actually wanted my pH higher, so it's fine with me, but it just didn't make sense based upon how my pool normally acts. Thank you for your answer!