I recently set up a 20-gallon freshwater aquarium and the first fish I introduced into it was a small convict cichlid (was this my first mistake?). After a couple days I was already worried, because although the water parameters all tested safe, the cichlid didn't seem very active, and just hid inside a rock formation. I then read that they can be shy and if they see no other fish in the tank, they will hide as they don't think it safe to swim about. So I introduced 2 tiger barbs into the tank (which might have been a mistake, the more I read about it), one of which is clearly alpha, spending most of his time chasing the other around, and occasionally bullying the cichlid, although the cichlid always holds his ground. However, over the past few days, the cichlid doesn't appear to be interested in eating and just stays resting along the gravel, and every once in a while tips slightly to one side. I'm not sure if he's sick or if the tiger barb's bullying is stressing him out, or both? Any advice would be greatly appreciated, thanks!