Green Spotted Puffer (Tetraodon nigroviridis) Breeding Guide

Breeding the green spotted puffer Tetraodon (Dichotomyctere) nigroviridis: brackish-only spawning, male egg- and fry-guarding, and why fry are very hard to raise.

Overview

The green spotted puffer, Tetraodon nigroviridis, is now also placed in the genus Dichotomyctere (Dichotomyctere nigroviridis). Young occur in brackish water while adults move into freshwater streams, rivers and flood plains. Breeding is not easy but has been spawned in aquaria, and it was bred under controlled conditions in February 2009 at the University of Florida using a variation of the ovarian lavage technique.

Sexing

There is no available information on external sexual dimorphism; the species is seemingly impossible to sex by external characteristics.

Breeding Setup

Spawning occurs only in brackish water. The tank should provide flat rock surfaces to serve as potential spawning sites, over a substrate where fry can later be tended. Stable brackish conditions consistent with the species' maintenance requirements are needed.

Spawning Behavior & Trigger

Courtship takes place near the bottom, and the eggs are laid directly onto the substrate or a flat rock. Spawning will only take place in brackish water, which is itself a key trigger and constraint.

Egg & Fry Care

The male guards the eggs, which hatch in around 6 to 7 days. As in many cichlids, the fry are then moved to a pre-excavated pit in the substrate, where the male continues to guard them. The fry are reported to be very challenging to raise because most foods are unsuitable; some success has been had using Cyclops nauplii, with newly hatched brine shrimp and mosquito larvae also suggested.

Common Challenges

The combination of a strict brackish-water spawning requirement, the inability to sex fish externally, and fry that reject most foods makes this a difficult species to breed in a home aquarium. Reliable larval rearing has chiefly been achieved in controlled or research settings rather than ordinary tanks.