yes do 2 today if you want to be really sure- one early in the day the other late and then do another tomarrow you'll garantee you've gotten whatever it tis out.
that is the BEST thing you can do- adding more chemicals won't help and worse it will dramatically increase the osmotic stress on your fish
that is the BEST thing you can do- adding more chemicals won't help and worse it will dramatically increase the osmotic stress on your fish