We took the gramma back because he isn't compatible with a fish my husband bought this week. Also, we just got an anemone and our clownfish gave our poor gramma heck whenever he got too close. That's what started the whole ich incident to begin with. He's beautiful so I know someone will buy him and give him a good home.
I've never used the medicine you bought today. I would read the directions carefully. Are you supposed to treat the entire tank or put him in isolation?
As far as your protein skimmer, is it foaming? Do you have a bunch of gunk sitting in your collection cup? If so, then it's working. Can you post a picture of it?
Yeah, there are a lot of things about teaching I disagree with, but working with the kids is so rewarding that I have to overlook a lot of the other stuff!