Hi all, can someone give me some advice. i have 60 litre tropical tank with tetris, swordtails and mollys. 1 of my swordtails has a swollen tummy. at first thought she was pregnant so got told by pet shop to isolate her in breeding net so have done that but she getting worse, she not eating she lying on her side as though she can hardly move. she looks so swollen. Whats wrong with her? My other fish are fine. no problems with them.