Newbie to pool chemistry


Apr 5, 2020
Alexandria, Louisiana
We moved about 2 months ago to a home with a pool. It is an IG, 15k gallon vinyl lined pool. We live in Alexandria, Louisiana. A couple days ago I tested the water (Sorry I don’t have the name of the kit but I believe it to be accurate...I think) and FC was 0, total alkalinity 120, pH 7.8, calcium hardness 300, and cya 40. I added a trichlor (I think it’s trichlor) tablet to the skimmer and shock/slam it with 14 oz of dry powder chlorine (calcium hypo 75%). I am going to test again today. I have a sand filter.

Question is: Do I pretty much need to have a 3” chlorine tablet (contains cya) in the skimmer all the time? Or, will that yield too much cya? Also, do I need to add smok/slam dry powder chlorine nearly every day? I also have 3” tablets of non-sustaining chlorine (no cya) and not sure at all when to use them.

I am a beginner so forgive me if I am not using the correct vernacular.

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