One of my Black Ruby Barbs has a chubby bottom. I assume it is a female because the analfin is partly black, while in the other 3 it is fully black. The fish used to be very active but is now hiding, breathing fast, and shivering. It has been doing this for the last 2 months at increasing periods of time. Now I treated before but this did not change the behavior. The tank is normal. All other fish are active. My question is what could be this behavior? The other barbs chase it around so I assume the fish is trying to avoid being chased? Is it stressed because it is the only female barb in the tank or it is sick? I had a previous barb with an internal abnormality that developed over time (obstruction that enlarged the rear of the fish around the anus) that had the same behavior. It died after a puncture from a bite as flesh was coming out and while moved its intestine popped out. So I am worried about this one, but the fish looks normal. A little chubby because I assume she is carrying eggs. Is it stress from being chased? The tank is a 20 gallon and is 100% stocked with other fish too (6 Harlequins, 1 Betta, 4 CPD, and 5 Corydoras). Stocking is based on Aq Advisor. Ordering more barbs would put the tank overstocked.