What a difference a year makes

[firepilot]

Hey All,

After discovering the site last year and doing it all ourselves last year I opened the pool yesterday. The pool was dirty but the water was clear. I went through the entire "Green Monster" experience last year. I am 2-3 weeks earlier this year and the water temp is 49 right now. I am a bit early here in North Idaho but will be gone a good chunk of April so went ahead and pulled the cover. I'd rather look at the pool than the cover anyway!

I did call the local pool shop and ask about opening early and they said to watch the ph due to farmers and acid rain in the area from field chemicals, this would lower PH and I would have to watch CH and TA as well. I told him its ok because my ph tends to climb a bit from aeration and i was told that wasn't possible.

On opening my chemicals as tested with my test kit were:

FC= 1.0 (I had added a gallon of bleach last week before I decided to go ahead and get it all running.
CC= .5 or less
TA= 100
CH= 240
PH=7.8
CYA=80

I ran the numbers in the pool calculator and rented a pump. I dropped the required amount of water to lower the CYA and this am it was done refilling.

I added another gallon of bleach just because and this am I have new results.

FC=8
CC=0
TA=100
CH= 240
PH= 7.8
CYA=35 !!!!!!!!!!!!

Last season the CYA was high and I managed with more chlorine as recommended. In addition my wife was experiencing a rash/bumps on her legs when she got into the pool. Last year our target FC level was around 7-8 I believe. She doesn't experience the same when using our hot tub.

I am hoping that getting the CYA level down and being able to use 3-4 for a target FC level will help the rash/bumps on her legs.

I am also wondering if keeping the PH down on the lower end of things would help. As always really appreciate any advice/experience others might have. We won't be heating the pool for at least another month so not a big issue right this minute. Common wisdom says if she can't enjoy the pool we might as well sell and move.

Thanks

Phil

 

[duraleigh]

pH of 7.2 - 7.8 is considered normal. If your pH is fairly stable around 7.8, I would leave it.

My pool likes 7.8 - 8.0. When it gets to 8.0 eventually, I only lower it back to around 7.6 and it takes a good while before it needs lowering again. If I lower it to 7.2 or 7.4, it seems to seek right back up to 7.8 rather quickly and there is no advantage in running at 7.2 over 7.8.

In short, I would leave your pH alone.

 

[chem geek]

I told him its ok because my ph tends to climb a bit from aeration and i was told that wasn't possible.

He doesn't know what he is talking about. Of course it's possible. Does he believe that the TA level of pool water is not "over-carbonated"? Such over-carbonation can result in carbon dioxide outgassing that raises the pH over time. This chart shows how much the water is over-carbonated with respect to air at various TA and pH levels.

 

[firepilot]

Thanks guys,

So far as a rash or such thing do you think having to maintain a higher FC level is more likely the culprit than the PH level?

Thanks

Phil

 

[chem geek]

It's more likely the pH since with the high CYA the high FC should not have been an issue unless the rash came from chlorine bound to CYA -- it's not very reactive so unlikely to be a problem, but with sensitivity one never knows.