Acropora spathulata Propagation Guide

Fragging and propagation of Acropora spathulata, a plate-based small-polyp stony coral with upward branches, increased by branch-tip cuttings in the reef aquarium.

Overview

Acropora spathulata is a small-polyp stony coral of the family Acroporidae, listed by WoRMS as an accepted species (Brook, 1891). In the aquarium trade it is recognised for a plate-like base from which upward-projecting branches rise, producing a table-with-towers shape. Like other Acropora it is a zooxanthellate coral whose tissues host symbiotic dinoflagellates that feed it through photosynthesis.

Reproductive Mode

Acropora reproduce asexually and sexually. In aquaria A. spathulata is propagated by fragmentation, which preserves the symbiotic zooxanthellae and coloration of the parent colony. Wikipedia notes that captive propagation of Acropora is widespread in the reef-keeping community.

Fragging / Asexual Propagation

Cut or snap an upward branch tip of about 2-5 cm with bone-cutters and bond it to a frag plug using cyanoacrylate gel or epoxy. The axial corallite at the branch tip drives regrowth, so an intact tip encrusts and extends fastest. Wikipedia reports finger-sized Acropora fragments can become medicine-ball-sized colonies in one to two years under good reef conditions.

Conditions for Propagation

Wikipedia states Acropora requires bright light, stable temperatures, regular calcium and alkalinity dosing, and clean turbulent water. Mount spathulata frags under high light and strong flow with stable alkalinity, calcium and magnesium and low nutrients to encourage encrustation and new branch development.

Sexual Reproduction

In the wild Acropora reproduce by annual synchronised broadcast mass-spawning, releasing buoyant packets of eggs and sperm into the water column for external fertilisation. This is generally not reproduced in home aquaria, where fragmentation is the practical method.

Common Challenges