4 lbs. of CYA will only take you to 20 which will not be high enough. If it were my pool, I'd just go ahead and add the other 4 lbs. which would take you to 40 and then be done with CYA. But, if you do that, you won't want to use the trichlor pucks because they will continue to add CYA. Once your CYA is at 40, your pool will hold chlorine through the day and you'll be able to test and add bleach in the evenings only.

For a pool with CYA of 40-50, your chlorine range is 3-6ppm.

You don't have to run the pump 24/7 unless the CYA is added to the skimmer or if you are experiencing cloudy water or algae issues. Otherwise, 8-10 hours per day is plenty. You can split this into two 4 or 5 hour sessions.

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