Pseudacanthicus pirarara (L024) Breeding Guide

Breeding the Red Phantom Cactus Pleco (L024): a large Pseudacanthicus cave-spawner with paternal egg care. Species data is thin, so genus-level practice is documented.

Overview

Pseudacanthicus pirarara (L024) is a large spiny cactus pleco of the genus Pseudacanthicus, which Wikipedia records as native to South America in the Amazon and Orinoco basins and the rivers of the Guianas. Species-specific spawning reports are scarce, so this guide follows the documented genus-level breeding biology described by Tropical Fish Hobbyist for cactus plecos, which it confirms as cave-spawners.

Sexing

For Pseudacanthicus, Tropical Fish Hobbyist reports that males develop longer pectoral and ventral fins and thicker pectoral spines, with a bulky, chiselled head, while females have a more pointed head. A ready female shows a markedly wider belly than the male. Sex can usually be told from around 15 cm.

Conditioning

Cactus plecos are carnivorous. Tropical Fish Hobbyist advises conditioning mainly on frozen foods and meaty tablets rather than vegetables; readiness is judged by the female's belly becoming much wider than the male's.

Breeding Setup

Tropical Fish Hobbyist recommends a tank of at least 100 cm length and 40-50 cm depth with caves, driftwood and stones with large openings, plus strong filtration. The breeding cave should be about 5 cm longer than the male's total length and only wide enough for him to enter with pectoral fins half-extended, with a rough interior surface so the clutch can grip.

Spawning Behavior & Trigger

Tropical Fish Hobbyist recommends warm water of roughly 27-32 °C, soft and neutral to slightly acidic, with water changes using soft, slightly acidic water to stimulate interest. The female enters the cave and lays eggs along the top while the male fertilises and then guards them.

Egg & Fry Care

According to Tropical Fish Hobbyist an adult cactus pleco female can produce about 500 eggs. Eggs hatch after six to seven days, and the larvae take about five days to absorb their yolk sacs under the male's care before dispersing into the tank, after which they need several small feedings daily.

Common Challenges

Tropical Fish Hobbyist warns that juveniles often start dying around 3 cm because of overcrowding, bacterial build-up and lack of space and hiding areas. Generous volume, frequent feeding and stable water quality are required to bring the brood through. As L024 is among the largest Pseudacanthicus, a very large grow-out is needed.