The common glass or ghost catfish, Kryptopterus vitreolus, has been swimming in numerous aquariums around the world for decades, albeit mostly under the misnomer K. bicirrhis (see https://www.aquariumglaser.de/en/fish-archives/a_new_name_for_the_ghost_glass_catfish_kryptopterus_vitreolus_en for details). We have the animal practically always in the stock.
One of the absolute routine measures in the everyday care of the fish is to examine it regularly in the beam of a strong flashlight for possible disease. In this context, one of our keepers, Martin Möller (who has a degree in biology), made the discovery that under certain light incidence, the glass catfish show a distinctly colorful iridescence. This is basically the same effect of light refraction that leads to the formation of rainbows. However, it is not easy to capture it photographically, because the interaction of light and movement of the fish must fit absolutely. After many unusable pictures, however, we finally succeeded in depicting the Möller effect. Fascinating, to say it with Mr. Spock!
For our customers: the animals have code 422005 on our stock list. Please note that we only supply wholesale.
Text & photos: Frank Schäfer