It can take a couple of weeks to turn swamp into swimmable. It's so much easier to keep it clean than to clean up a swamp-- been there done that Why did you add 3lb of CYA? And yes CYA does take a few days to fully dissolve, ideally you should add a small amount, and wait a few days before testing... much better to undershoot it.. Good luck and be patient it will get better if you keep at it.