Diptail Pencilfish Breeding Guide

Nannostomus eques deposits eggs in single batches on the underside of plant leaves. Fry are free-swimming by the 5th-6th day and need very small first foods.

Overview

Nannostomus eques is a small pencilfish from the central and upper Amazon in Brazil, Peru and Colombia, also reaching the Orinoco drainage and Guyana. Seriously Fish records a size of 25-35 mm SL, and the species characteristically swims at an oblique angle. It is an egg-layer that, unusually for the genus, deposits eggs on the underside of plant leaves.

Sexing

Adult males are more colourful and usually slimmer than females, and possess an enlarged anal fin (Seriously Fish). Females are rounder-bodied, especially when carrying eggs.

Conditioning

The species is a micropredator; condition adults with daily small live and frozen foods such as Artemia nauplii, Moina and grindal worm, alongside fine dried foods. Soft, acidic water suits it: Seriously Fish gives 22-28 C and pH 4.5-7.5, while FishBase lists pH 5.0-6.0 and hardness 5-12 dH for spawning conditions.

Spawning Behavior & Trigger

Unlike most congeners, Nannostomus eques deposits its eggs in single batches on the underside of plant leaves rather than scattering them freely (Seriously Fish). Fine-leaved plants therefore provide the spawning sites.

Egg & Fry Care

Fry become free-swimming by the 5th or 6th day. According to Seriously Fish the first food should be Paramecium or a proprietary dry food of sufficiently small grade (about 5-50 microns), moving on to Artemia nauplii once the fry are large enough.