Bannertail cory

Corydoras robineae

Also known as Flagtail cory

FreshwaterFish

Care at a glance

Temperature: 73–79°F (23–26°C)
pH: 6.0–7.5
Adult size: 2.6 in (6.5 cm)
Minimum tank: 20 gal (75 L)
Temperament: Peaceful
Social behavior: Schooling
Swim level: Bottom
Difficulty: Medium
Breeding: Hard
Rarity: Common
Origin: Rio Negro basin, Brazil (South America)
Family: Callichthyidae

Overview

Keep them in a group of at least six, more if you can, in a tank of 75 liters or larger. Smaller groups make them shy and stressed, so they hide instead of foraging out in the open. They are peaceful bottom dwellers that sift the substrate for food, so feed sinking pellets and small frozen foods like daphnia or bloodworm. Water should sit between 23 and 26 C with a pH from 6 to 7.5, soft and slightly acidic suits them best. They are sensitive to poor water quality and dirty substrate, which erodes and infects their barbels, so keep the sand clean and stay on top of water changes. Pair them with small, gentle tankmates.

In the wild

Bannertail cories come from the Rio Negro basin in Brazil, soft and slightly acidic blackwater stained dark by tannins, with sandy beds and leaf litter. To match that, give them a tank of at least 75 liters with a smooth sand or very fine substrate, some driftwood and dried leaves, and gentle shade from plants. Keep the water between 23 and 26 C and a pH from 6 to 7.5. They like well oxygenated water with a bit of current, so aim some of the filter flow across the bottom.

Good to know

This is a cory catfish in the family Callichthyidae, reaching about 6.5 cm. Sources disagree on size, with FishBase listing close to 4.4 cm standard length while care guides report roughly 6 to 7 cm total length and up to about 8.5 cm for large females. It is named for the bold stripes on its tall caudal fin, the bannertail. Like other cories it has paired sensory barbels around the mouth for finding food in the substrate.

Did you know

Those delicate barbels around the mouth are working sensors, not decoration. The fish drag them through clean sand to taste and feel for buried food, which is why a smooth, fine substrate matters so much. On gravel or in a dirty tank the barbels wear down and get infected, and a cory with stubby, damaged barbels has lost much of how it finds a meal.