Multiple posts for the same question aren't going to get you helped any faster, it's just going to get people irritated with you. Please do the rest of us a favor and try to observe decent netiquette.
I'd reccomend a salt treatment for your fish. Add 1.5-2 tsp salt per gallon (table salt will work just fine) and turn up the temp as dattack mentioned.
Is the tank he's in now cycled? If not, he's going to be in worse shape then he would be if you left him untreated in the main tank. I would reccomend you take some of the filter media from your existing tank and add it to the filter of your hospital tank (if you haven't done this already...), if your filter setup prevents this, then I would reccomend you move your sick fish back to the main tank and treat him there.
HTH,
Josh