When choosing a protopterus, preference should be given to individuals with clean skin, free of visible ulcers, wounds, or areas with unnatural plaque. It is important to assess the fish's activity: a healthy protopterus should show curiosity, react to movement near the glass, and periodically rise to the surface for a gulp of air. Avoid specimens that appear emaciated, have a sunken belly, or constantly lie on their side without apparent reason. — pay attention to the integrity of the fins, which should show no signs of splitting or erosion; — ask the seller how the fish accepts food, as healthy individuals usually have a good appetite; — note that young individuals may have external gills, which is normal, but in adult fish, their presence may indicate developmental or adaptation problems. Since this species is territorial and aggressive, fish are almost always kept individually in stores. If you see several individuals in one aquarium, carefully inspect them for bite marks or fin damage caused by intraspecific aggression. Given the potentially large size of an adult protopterus, assess in advance your readiness to provide it with a spacious aquarium with a secure lid, as these fish are prone to escaping.