Orinoco flagtail prochilodus

Semaprochilodus laticeps

Also known as Colombian flagtail prochilodus, Royal flagtail

FreshwaterFish

Orinoco flagtail prochilodus (Semaprochilodus laticeps) — The Wet Spot Tropical Fish · Used with permission

Care at a glance

Temperature: 73–82°F (23–28°C)
pH: 5.5–7.5
Adult size: 17.3 in (44 cm)
Minimum tank: 264 gal (1,000 L)
Temperament: Mostly peaceful
Social behavior: Social
Tankmates: Tankmates with caution
Swim level: Middle
Difficulty: Difficult
Breeding: No record
Rarity: Rare
Origin: Orinoco basin, Colombia and Venezuela
Family: Prochilodontidae

Overview

This is a large, migratory grazer that shoals in the wild, so it does best as a group, but only in a very big tank, since adults are active swimmers approaching 44 centimeters. It grazes algae and detritus from surfaces with a sucker-like mouth, and while it is mostly peaceful, it can squabble and jostle, so treat tankmates with caution and give it space and current. Feed a mainly vegetable diet of algae wafers, spirulina, and sinking greens alongside some frozen foods. This is a serious commitment that needs around 1000 liters or more, really a project for monster-fish keepers.

In the wild

The Orinoco flagtail comes from the Orinoco basin of Colombia and Venezuela, where it runs the main river in vast shoals and feeds on the film of algae and detritus coating the bottom. In a tank it wants length and strong, oxygen-rich flow more than decor. Keep the water warm and soft to neutral, from 23 to 28 C at a pH of 5.5 to 7.5, with heavy filtration to handle its output.

Good to know

Semaprochilodus laticeps is a member of Prochilodontidae, the flannel-mouth characins, and at about 44 centimeters it is the largest of the flagtails. Its protrusible, rubbery mouth is ringed with fine teeth for rasping algae and detritus off rocks and wood. It is not bred in aquaria, since it is a long-distance migratory spawner, so captive reproduction is essentially unrecorded.

Did you know

In the wild these fish gather into enormous spawning shoals that surge up the river each year, a migration so dense that local fisheries are timed around it. The banded tail fin that gives the flagtail its name flashes through the whole run.