Welcome to the forum.
Your CC at 3 ppm needs to be addressed pretty quickly.
You will need about 10 gallons of 6% regular unscented bleach. Circulate for 24 hours and check the Cl ppm.
Download Mike W. Smith's Bleach Calculator. (Do a search for him in the member's list) . Then do another calculation to see how much more you need to get the Cl ppm back up to 5 ppm. The idea is to get the CC down to less than 0.5 ppm.
The CYA needs to be added as well. The calculator again will help.
Keep us posted with your numbers, and we can help you further.
Pat
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