Okay, I know it might not be a disease, but it's still important. My betta PK, has been acting sluggish for the last couple days. I just cleaned him today. He's a very happy fish even if he lives in a small tank. I play with him to stop him from feeling depressed and lonely.
Anyways, his symptoms are: slugishness, slow reaction time and he's sticking his left fin out and letting it hang awkwardly when idle.
Could he have pulled a muscle or torn a ligament? He's very active. The other day after playing with him, whilst settling into bed, I heard a loud ping sound coming from his tank. Could he have injured himself? I hope it isn't a hidden disease or broken bone.