Porthole rasbora

Rasbora cephalotaenia

Also known as Cephalotaenia rasbora

FreshwaterFish

Porthole rasbora (Rasbora cephalotaenia) — The Wet Spot Tropical Fish · Used with permission

Care at a glance

Temperature: 72–81°F (22–27°C)
pH: 5.0–7.0
Adult size: 5.1 in (13 cm)
Minimum tank: 42 gal (160 L)
Temperament: Peaceful
Social behavior: Schooling
Swim level: Middle
Difficulty: Medium
Breeding: No record
Rarity: Rare
Origin: Malay Peninsula, Singapore, Borneo and Sumatra
Family: Danionidae

Overview

The porthole rasbora is a large, streamlined rasbora that cruises the upper half of a long tank, so give it space and keep a group of at least six for a settled, confident shoal. It is peaceful despite its size and mixes well with other calm blackwater fish such as similar rasboras, gentle barbs, loaches, and small gouramis. It glides steadily rather than darting and takes all the usual foods: quality flake and pellets, plus frozen and live items. Because of its adult length and active habits, plan on a tank of around 160 liters or more with plenty of open swimming room.

In the wild

It ranges widely across Sundaland, in blackwater streams and peat swamps of the Malay Peninsula, Singapore, Borneo and Sumatra, over soft substrates with driftwood, roots, and leaf litter under dim light. Give it a long, shaded tank with soft, tannin-stained water, sandy substrate, and tangles of wood. Keep the temperature between 22 and 27 C and the pH from 5.0 to 7.0.

Good to know

Rasbora cephalotaenia, family Danionidae, is one of the larger rasboras, growing to about 13 centimeters in the wild though usually less in aquaria. A dark lateral line runs the length of its body and breaks into a row of separated marks that the trade reads as portholes, giving the common name. Its breeding behaviour is not documented in aquaria, but like its relatives it is presumed to be an egg-scattering spawner.

Did you know

The row of dark blotches along its side, spaced like the portholes on a ship's hull, is what earned the fish its common name; wild individuals can reach roughly twice the length of the small rasboras most keepers picture.