New Pictures of the fish

[Flatcoatluver]

Does he have a heater in his tank? Sometimes extra heat can help aid some bettas that aren't doing too well.
Good luck with your boy! I hope he begins to feel better. =)

No he doesn't have a heater, but what if I turned on the light? The only fish that has a heater is the cichlid.

[Chilli]

I find that lights in the tank don't heat all that well... if I were you, and knew he was going to stay in the 10g, I would go ahead and invest in a heater. Bettas do like the temperature to be a bit above 75 degrees, but can do fine in cooler temps.