A glass catfish is a type of freshwater fish that is found in the rivers of Africa and Asia and is known for its completely transparent body that fully reveals its bone structure and organs to plain sight. The unique appearance of the fish makes it a popular aquarium pet, with the fish normally kept in a school size of six or more. The glass catfish has two protruding barbels as whiskers off the side of its face, and it averages 5.9 inches (15 cm) in length. The scientific name of the common Asian variety of the fish is Kryptopterus bicirrhis, with the first part of the name referring to the fish’s complete lack of a dorsal fin.
The glass catfish lives in Borneo, Sumatra and the Malay Peninsula, and it is found in large rivers and drainage basins. It lives in water with relatively moderate to low temperatures, and it prefers areas near the shore in cloudy water. When in the wild, it primarily eats water bugs and will sometimes consume smaller fish.
It is often confused with the ghost catfish because the two have an almost identical appearance. As such, it was not known until 1989 that the two fish are actually distinct species. The ghost catfish is formally known as Kryptopterus minor. In Cambodia, both the ghost and glass catfish are known as trey kes park, and they are used in the making of the fish sauce prahoc. In the Malay Peninsula as well, the two fish share a common name, lais tipis, with the glass catfish alone being called lais limpok.
Within the Kryptopterus genus of catfish, there are 19 species that all have transparent body types that lack a dorsal fin and live in the freshwater rivers and basins of Southeast Asia. There also are African glass catfishes that have larger bodies and shorter overall barbel whiskers. The glass catfish become white and opaque when they are ill, dying or already dead.
As aquarium fish kept as pets, glass catfish eat flakes, brine shrimp and different varieties of worms, including blood worms and tubifex worms. They need to kept in large schools or they will become very shy and retreat into hiding, which affects their eating habits. The fish prefer to have dark-colored plants and other foliage in the tank to hide around, and most of their activity occurs during the daytime. Glass catfish are prone to bacterial infection that starts as white patches, and they should be quarantined in a separate tank when first purchased, so that the owner can watch for signs of disease. Once the glass catfish are moved into a main tank, good companion fish for the catfish school includes male guppies, rainbow fish and small cichilids.