The tail has never ever healed completely. I'm not sure what I could do to make life easier on him, I know if there are 2 males to 1 female severe aggression can be an issue but I think they are all male. His belly also developed a red line running from chin to anal fin, I've just attributed it to stress, but have recently noticed his belly, all of there bellys but his is the worst; appears bloated. I've only recently learned about fish getting internal worms so I've been a bit concerned that's a possibility and am interested in finding a treatment that won't affect my bio and that I don't have to remove carbon for, if possible, I've read prazi pro fits the bill. Also once the tank is treated for worms jic would it be a good idea to add a few more guppies so there 'school' is bigger? I