Korthaus rasbora

Pectenocypris korthausae

Also known as Pectenocypris korthusae, Comb rasbora, Orange spot torpedo rasbora

FreshwaterFish

Korthaus rasbora (Pectenocypris korthausae) — The Wet Spot Tropical Fish · Used with permission

Care at a glance

Temperature: 73–82°F (23–28°C)
pH: 4.5–6.5
Adult size: 1.7 in (4.2 cm)
Minimum tank: 14 gal (54 L)
Temperament: Peaceful
Social behavior: Schooling
Swim level: Middle
Difficulty: Medium
Breeding: No record
Rarity: Rare
Origin: Peat swamps of Sumatra and Borneo, Indonesia
Family: Danionidae

Overview

Keep this slender blackwater rasbora in a school of eight or more with other soft-water species such as small rasboras and kuhli loaches. It is peaceful and hangs in midwater, feeding on fine drifting foods, so offer small frozen and live items like cyclops, daphnia, and baby brine shrimp alongside finely crushed dry food. Soft, acidic water is non-negotiable, and the fish loses condition in hard, alkaline conditions. A dim, planted tank of around 54 liters over leaf litter works well for a group.

In the wild

The Korthaus rasbora lives in blackwater peat swamps and slow forest streams of Sumatra and Borneo, in tea-dark, soft, acidic water. Recreate that with botanicals and leaf litter, a dark substrate, dim light, and gentle filtration through peat or almond leaves. Hold it warm and acidic, 23 to 28 degrees Celsius with a pH of 4.5 to 6.5.

Good to know

Pectenocypris korthausae belongs to the danio family, Danionidae, and reaches about 4 centimeters. Kottelat described it in 1982 and named it for the German aquarist Edith Korthaus, who helped collect the first specimens; the genus name means comb carp, for the fine, comb-like gill rakers it uses to strain tiny food from the water. Its breeding is not on record.

Did you know

It feeds like a filter, drawing plankton and fine particles out of blackwater through gill rakers combed as fine as any plankton-straining fish, a basking-shark trick shrunk to the size of a matchstick.