Butterflyfish

The butterflyfish has a highly distinctive look. Viewed from above, it is easy to see why it bears its name. The enlarged pectoral fins resemble wings and serve two key functions: camouflage and assistance in jumping. The fish can remain still at the surface for long periods, disguised as a fallen dry leaf. When needed, a sharp movement of the broad tail allows it to leap out of the water over a considerable distance, either to hunt a passing insect or to escape a predator. Adults grow to about 12 cm long, but their large fins and tail make them appear more substantial. The body is grey with dark pigmentation throughout, and the fin rays appear as dotted lines.

Pantodon buchholzi originates from regions of West Africa. It is found in modern countries including the Republic of the Congo, the Central African Republic, Chad, Nigeria, Sierra Leone, Niger, Gabon and others. The fish inhabits the basins of the Niger and Congo rivers, Lake Chad and the Ogooué River, preferring numerous lakes, swamps and slack waters of small rivers and streams where dense aquatic vegetation and fallen wood are abundant.

The butterflyfish is twilight-active and relatively inactive, becoming mobile only to hunt surface insects or escape predators. It is a reasonably peaceful species, but may show aggression towards other fish that live at the surface. Any small fish that fits in its mouth will be eaten. It is incompatible with species that bite fins, such as barbs.

Tank size depends on the number of inhabitants: for one or a pair, at least 80 L is recommended. The lower level can be decorated as desired, for example with dark substrate and plenty of wood. The surface zone should include some floating plants, but they should not cover the entire area. Open water surface must account for at least half the total surface area. Optimal water conditions are slightly acidic pH and low carbonate hardness. If desired, a few dried leaves can be added; as they break down they will enrich the water with tannins and give it a characteristic tea tint. Replace these leaves every two weeks or more often. Water movement should be minimal, which limits filter choice. Consult a specialist before buying equipment to find a model that combines high flow with minimal internal current. The basic equipment also includes a heater, air pump and light. Tank care consists of weekly water changes of 15–20% of the volume and regular cleaning of the substrate and glass.

This fish eats only meat foods, live or frozen. In the home aquarium it takes bloodworm, brine shrimp, small worms and various flying insects of suitable size, such as flies or mosquitoes. Feeding occurs only at the surface; any food that sinks will be ignored.

Breeding this fish at home is challenging but possible. If other species are kept in the main tank, a separate breeding tank is needed. Fill it with water from the main tank. Use clusters of floating plants that need no bright light; substrate may be anything or absent. You will need a simple sponge air-lift filter and a heater. Natural light from the room is sufficient. Place a pair in the prepared tank. Over three weeks, gradually reduce the water volume to about half the original amount. By this point, water pH should be slightly acidic and temperature maintained at 26–28°C. Then over two to three days, add small portions of cool water to lower the temperature to 23°C. This mimics natural seasonal change from drought to rain. The female then spawns, laying up to a hundred eggs daily over several days. The eggs are lighter than water and rise to the surface immediately. Since parental care is weak, carefully transfer the eggs to a separate temporary container to prevent the parents eating them. When spawning ends, return both eggs and parents to their original places. Fry appear in three to four days and can only eat microscopic live food. The fry do not actively search for food, so you must deliver it to them with a pipette. Feeding the young is the main difficulty in breeding butterflyfish.

Balanced feeding and proper tank conditions are the best prevention for disease in freshwater fish. If the first signs of illness appear—changes in colour or behaviour—first check and correct water parameters and quality if needed, then begin treatment.

When choosing a butterflyfish, first observe its behaviour in the shop. A healthy fish should stay at the surface, showing interest in its surroundings. Avoid specimens that look thin, have damaged fins, cloudy eyes or unusual spots on the body. A key sign of vitality is active feeding response: ask the seller to feed the fish in your presence. If it ignores the food or seems lethargic, do not buy it. Be aware of these risks and characteristics: — butterflyfish are specialized predators and may refuse dry foods in the shop, preferring live or frozen foods; — during transport ensure adequate air, as the fish is very sensitive to water quality and oxygen levels; — damage to the body or fins may indicate recent fights with tank mates or poor keeping conditions, often leading to secondary bacterial infection after moving to a new tank.