Never mind. I checked today and there are no spots anymore. I doubt the medicine acted that fast, so it must have been something else, but its gone. Thanks for the help. There are two jouvinial goldfish (Fantail). They came from Walmart ( I know, the worst place to go) and the tank is a 5 gal. Water parameters are all good, just did a test yesterday. I forgot to write down the numbers.... Just did a pwc today too.