Few questions for a new pool owner

[Mtuccolo]

I'm following the trouble-free pool formula for success and I have a few questions.

1. My CYA is a normal range but went down about from 50 to 45. I thought the only way To decrease cya was water exchange?

2. My pH recently went up from 7.6 to 8 what causes the pH to increase? I did add acid according to the pool math calculator to bring the pH back down.

3. What is combined chlorine and what causes it to accumulate?

Thanks you guys have been great!

 

[YippeeSkippy]

I'm following the trouble-free pool formula for success and I have a few questions.

1. My CYA is a normal range but went down about from 50 to 45. I thought the only way To decrease cya was water exchange?
The cya is either 40 or 50, there isn't a halfway. And since its such a subjective test .....well... just make sure you're testing with the sun at your back, holding the vial waist high. It helps to look away and back at the dot now and then to refresh your eyes.

2. My pH recently went up from 7.6 to 8 what causes the pH to increase? I did add acid according to the pool math calculator to bring the pH back down.
Aeration, kids splashing, SWGs and the like will often raise pH. All you can do is lower it as necessary, and check your TA that it isn't too high as it will pull the pH up if it is.

3. What is combined chlorine and what causes it to accumulate?
combined chloramines are the used up FC that is killing the cooties. Sunlight helps it dissipate, as does extra FC. People who say a pool is safe because they smell chlorine are actually entirely wrong. If you have a strong chlorine smell, your FC is overwhelmed by the contaminates in the water (sweat, pee, lotions...) and the pool actually needs MORE chlorine.

Thanks you guys have been great!

Thanks, we try