I've had my betta, Neptune, since last Saturday. He hasn't been eating at all..even when I offer him food. Currently, he's in a 1.5 gallon tank with gravel, a plant, a log, and a filter. I've bought a heater and it's in the mail. I'm really worried that he's sick. After I came home today, I noticed a large lump under his chin. I've never seen it before. The tank temperature is around 72, but when the heater comes it will bump the temperature to 78. I've posted some pictures below. Help! I really want him to stay alive :( Please help!
Is it a disease? Or is it him tiring. He's always swimming around...I've never seen him rest. Even with the bump he's swimming around...Does it look like anything serious?
I've uploaded a picture of what he looked like before the bump came, after I noticed the bump, and a picture of the entire tank.
Thanks a bunch!