Briareum violaceum (Star Polyps) Propagation Guide

Propagating Briareum violaceum, the green star polyp, by dividing its encrusting purple mat and cutting the rock it spreads across.

Overview

Briareum violaceum is a soft coral in the family Briareidae and an octocoral of the order Scleralcyonacea. In the aquarium trade it is cultivated as green star polyp, or GSP, and shows fluorescing polyps that reveal themselves under actinic light. Commercial specimens are frequently mislabeled, and the marketing name Pachyclavularia violacea is often applied to corals of this genus, which has created lasting taxonomic confusion.

Reproductive Mode

Star polyps grow from an encrusting purple mat that advances over rock, and propagation in the aquarium is asexual, achieved by dividing that spreading mat.

Fragging / Asexual Propagation

Because the colony consists of polyps emerging from a connecting purple mat or stolon, a frag is made by cutting the mat between sections of polyps, or by cutting the rock the mat has encrusted, and then attaching the piece to a clean plug or rock until it re-attaches and the mat resumes spreading.

Conditions for Propagation

Briareum is hardy and spreads readily, so frags establish quickly under the lighting, flow and water parameters recorded for this species in the knowledge base. The fluorescing polyps confirm a healthy, settled frag once they open over the mat.

Common Challenges

The vigorous, encrusting growth that makes Briareum easy to frag also lets it overrun neighbouring corals, so frags should be placed where the mat can be contained. Identification is also unreliable in the trade because diverse specimens are sold under a single label.