I am at work so I can't check to be sure, but I think the Taylor titration tube for the CYA test only tests as low as 30 ppm? So no CYA tested by the Taylor kit doesn't necessarily mean no CYA.
I add CYA with dichlor through my filter, and it always takes 2-3 days for it all to dissolve and give me an accurate reading. I am not sure about the sock, but if its a granule I would think it would take a similar amount of time.
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