I would discount weak bleach and probably the size of your pool....but you can doublecheck.
What I would count on is that you never got to 25 because the organics in your water were consuming the Cl as you introduced it. So (probably) what should've been 25ppm and ends up 13.5ppm is from organics in your pool. You need to shock it again.
In the evening, test and target more than 25ppm (Say about 30-35). That should ensure you reach breakpoint (shock)and get the CC's and organics out of your pool. The next morning....test again. If you've still lost a lot of Cl overnight, I would do it a third time. Only when you can hold Cl overnight with somewhere around a 10% loss or less would I consider backing then Cl down and keeping it around 8-15ppm
PS - ditch the pucks...your high CYA and Ca (no Cal Hypo, either) indicate you should use only bleach the rest of the Summer.....or do a partial drain.
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