We treated him with the antibiotics and he perked up. He even ate two meals in a row. Then he took a nose dive and didn't make it through the following weekend.
It was sad, but in some ways a blessing because he was so unhappy for so long.
It's been a couple of weeks and I soaked everything he came in contact with with bleach and let it air dry. I've filled up the tank and got the temp just right, so I think I may be ready for a new fish.
I'm still pretty bummed but I miss having a happy fish swimming around keeping us company. I'm also seeing the folly of picking a user name based on an animal who has a life span of 2-5 years. I like the name though, so there you have it.
Anyway, thank you for the help. It helped, and if nothing else I know I tried to save him in every way I could.