Corydoras julii (Leopard Corydoras, Julii Corydoras)
Corydoras julii and Corydoras trilineatus are very similar and frequently confused by both hobbyists and retailers. Both have a pale silvery-white body with a pattern of fine black spots on the flanks including a neat row along the midline of the fish bordered with white and running from behind the gill cover to the base of the tail. Both also have a dark patch on the dorsal fin. When compared side by side, Corydoras julii tends to be more delicate in build and the pattern of spots is much finer, with each spot being quite distinct. Corydoras trilineatus is more robust in build and the spots commonly form squiggles and bars.
Fish information (behaviour and breeding):
A peaceful, schooling fish. Best kept in groups of six or more. Corydoras do best in aquarium with other small, peaceful community species such as tetras, danios, small barbs, gouramis, etc. Dwarf cichlids are sometimes antagonistic towards these fish, and that combination is not recommended. Although Corydoras are often purchased as "scavengers" it is important that they are regularly fed on a good-quality catfish food.
Corydoras spawn in the same basic way regardless of species; the key things for the aquarist are to replicate the natural water chemistry parameters as carefully as possible and then to thoroughly condition the adults with plenty of live or frozen foods such as bloodworms and clean tubifex worms. When the females are ready to spawn they will be obviously swollen with eggs. In many cases specific spawning triggers are required, typically early morning sunshine and the addition of slightly cooler water to the tank to mimic a rainstorm.
Spawning takes place across an hour or more, with a single female being attended by multiple males as she searches the aquarium for clean, flat areas to deposit her eggs. The males fertlise the eggs that are held in a pouch-like structure formed by her pelvic fins, and the she will carefully place them onto a stone, plant leaf, or pane of glass. Up to 200 eggs will be produced. The eggs hatch within 5 days, and once free swimming the fry will eat Artemia nauplii and liquid fry foods. Corydoras fry are generally easy to rear but relatively slow growing, and both eggs and fry can be prone to fungal infections, so putting some anti-fungal medication in the water may be useful.
|Distribution||Brazil, Lower Amazon River and coastal rivers|
|Size||Up to 5.2 cm|
|Water Parameters||Adaptable, but avoid extremes|
Useful sources of information:
Corydoras benefit from being among the most written about catfish, and there are lots of excellent books to choose from, including:
- Aqualog - All Corydoras
- Aqualog - Corydoras All C Numbers - Brand New
- Breeding Corydoradinae Catfish
- Identifying Corydoradinae Catfish