One of my Denison Barbs is looking pretty bad. His/her (not sure of the sex) body is distorted and bulging at the bottom. I'm thinking maybe it's a bit backed up? If its female, maybe she's carrying eggs. Noticed it yesterday, but it was still coming up for food and active so I wasn't too concerned. Today it doesn't look any better, and (s)he is swimming funny, floating off here or there and flipping over a bit, hanging out on the bottom, etc. it's not looking good.
Should also mention that I've had him/her for a year now.
Here are some photos: imgur: the simple image sharer
Any ideas/advice would be much appreciated!
The tank is a 55 gallon planted community tank, temp around 74, ph 6.6. 3 fluval c3 filters.