I have this tiger barb that started acting weird. At first I noticed that it was swimming at an angle and with a more vigorous motion and its belly had a slightly different shape than the others. Two or three days later I noticed that the bulge became bigger and the fish is only swimming vertically in circles all the time. Any idea what it could be? Will this affect the rest of the fish?
Here's a picture of the fish
https://dl.dropboxusercontent.com/u/6712827/P1010288.JPG
Here's a picture of the fish
https://dl.dropboxusercontent.com/u/6712827/P1010288.JPG