Goldfish is sick, help?

I was pretty sure it had ick (white spots on fins) so I started treating him with Wardley's ick medicine. Its been 2-3 weeks and the ick is still present and now the fishy has fin and tail rot. His tail is even bleeding some. He still has a good appetite. I'm doing almost every other day 25%-50% water changes. He is all alone in a 5 gallon tank with filtration (although I took out the carcoal as directed by the medication). Is there something out there that is better medicine for him that will treat the fin rot and the ick both at the same time? This fishy is like 7+ years old!