It seems that worms carry either parasites or bacteria to the fish's intestinal tract, causing it to bloat up like a balloon. To date there is no known cure. The best way to avoid this condition is to refrain from feeding live worms, even if you think they're adequately washed. Treat these conditions as you would for any other fish. Even in tank raised fish, the stress of shipping may allow a parasite that was lying dormant in the fish's tissues to take hold.
Prevention is always the best medicine, so treat all arrivals and never feed black worms or tubifex.
Apistogramma cacatuoides male in aquarium. If the above conditions are met, breeding apistos should be no problem. As nature takes it course, you'll see the female turn bright yellow with black markings as she approaches spawning condition and then maintain that pattern while tending eggs and fry. You may fail to see the fry at first, as they are tiny and tend to hide in the gravel, but don't worry. They'll feed off organisms in the sponge filter and gravel for the first day or two.