Okay so, I'm still a little worried. He's eating a bit more, but he's still wicked lethargic. Right now he spends most of his time in the corner by the heater. One time he came out and swam by and I thought I saw something weird on him, I had to use a flashlight to get a better view because he's SO black. He MIGHT have a bit of a swollen belly - it's so hard to tell. Here's my biggest concern. He's always had a bit of a reddish/green tint to his scales if you get a light on him, but when I was looking at him today it seems like there might be a lot more red now, could it be Velvet?
Would it hurt to treat him for it if he doesn't have it? I don't want to do something unnecessary but I don't want to just let him be sick if I could help prevent it.