Microglanis iheringi Breeding Guide

Breeding the South American bumblebee catfish Microglanis iheringi: conditioning, hardscape triggers, scattered eggs and brine-shrimp fry care.

Overview

Microglanis iheringi, the South American bumblebee catfish, is a small black-and-yellow banded catfish of the family Pseudopimelodidae. It is an egg scatterer, and although it is generally regarded as difficult to breed, successful spawnings have been documented in home aquaria.

Sexing

External sexing is difficult. In documented spawns the only clear distinction was body shape: a slimmer male pursuing a markedly plump, well-rounded female, with females appearing noticeably fuller when carrying eggs.

Conditioning

Condition adults well so that females become rounded with eggs. Reported successful conditions used a pH between about 6.5 and 7.8 and a temperature around 78 F (about 25 C). Regular partial water changes were part of the maintenance routine in documented cases.

Breeding Setup

Provide clusters of rounded river rocks and crevices where eggs can fall out of reach, together with structure such as tubes and mesh. Because eggs are non-adhesive and scatter, an egg-protection layer (for example a false bottom of marbles or a grid) helps keep them away from hungry adults.

Spawning Behavior & Trigger

In documented cases spawning followed changes to the physical environment, such as moving the tank or rearranging the rockwork, combined with the presence of a well-rounded female. The fish scatter their eggs among the rocks rather than tending a fixed nest.

Egg & Fry Care

Eggs are small, roughly 1-2 mm, and transparent green. Hatching is rapid, typically within about 18 hours and under 24 hours, with hatch time shortening at higher temperature. Free-swimming fry swim almost constantly and shelter near the surface; they accept newly hatched or decapsulated brine shrimp, plus microworm and vinegar eels. Raise the fry much as you would tetras.

Common Challenges

The two main hurdles are the difficulty of sexing the fish reliably and protecting the scattered, non-adhesive eggs from predation before they hatch. Fertility of a clutch can be partial, so a protected substrate and prompt feeding of small live foods improve fry yield.