I just wanted to write a quick update - I don't think the fish is going to make it. Throughout the day, he has looked increasingly worse. As of this morning, he was floating vertically....now, he is laying on his side on the bottom of the tank. His respiration is very labored. His color is now a yellow/grey....he is supposed to be more of a reddish color. Thank you for all of the information and support. I don't have it in me to decide to euthanize him, but I can't help but feel like it might be the most humane option.