The corys are doing well And eating at every opportunity lol. I hadn’t thought of that but your absolutely right. I figured like you say a week after any symptoms so this just makes the total dosing day’s longer. But at half dose that probably could have been expected.I just want to remind you that a half dose of any med may take much longer than a "full" dose. I often dose half in the am & half again in the pm (or vice vs) just to be sure fish can tolerate the med. Any signs of distress & it's a big WC & back to half dosing. How are the corys doing?
While we're all staying home, maybe try upping the dose to a full dose in the am. Check often & be ready to do WCs if they seem stressed out (hanging at the surface, breathing fast, darting around, etc.) We all want this to be over for you so we can get back to pretty plants, tank & fert discussion
Like I said I'm not a super fan of the med you have but just keep going! & when it's time to remove it go fairly slow because of the salt & TDS; carbon will remove the other stuff.