myth that salt cannot be used on this species of fish as a means of parasite medication. Salt can be added to the water of the Corydoras catfish in order to rid the fish of ich. These fish are fairly easy to keep, being peaceful, hardy, active and entertaining. Occasionally they will dart to the surface, sticking their snout above the water for an instant to take a breath of air. This behavior is perfectly normal and is not an indication that anything is wrong with the fish. However, if this is done in excess, it can indicate poor water conditions. Where investigated, Corydoras sp. have been shown to be diurnal and crepuscular rather than nocturnal and activity can even peak at twilight. Corydoras are a very popular choice for a community aquarium and are widely kept throughout the world. Their longevity in the aquarium is noteworthy; C. aeneus is said to have lived 27 years in captivity and 20 years is not too uncommon. Species There are currently 161 recognized extant species in this genus, as well as one known extinct species: See also List of Corydoras species List of freshwater aquarium fish species References Catfish genera Freshwater fish genera Fishkeeping Callichthyidae Paleocene fish Taxa named by Bernard Germain de Lacépède Extant Thanetian first appearances