Within the last 2 weeks my senegal has begun to develop a "bulge" near its tail. I waited to see if it would go down and have kept to my water changes and what not but it does not seem to go away. any help would be appreciated. He shows no signs of irritation and still eats normally. I can't honestly say whether not he has been "releaving himself" because of the other 3 bichirs I have with him.