First thing to do is get a test kit. Order one today. Link-->
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We recommend liquid chlorine or a salt water chlorine generator. You can use tabs, but they add CYA. The only way to get CYA out is to replace water. Continual use of tabs require water replacement, when CYA gets to high.
We are early in the season, so it is fine to use some tabs now, as your CYA is likely low, but without a test kit, we don't know. So best course of action is to turn off the chlorinator and add 3ppm of liquid chlorine a day until your kit arrives. Then test and post a full set of results.
Can you post a picture of your pool water today, and fill out your signature.
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