Pavona cactus (Lettuce Cactus Coral) Propagation Guide

Propagating the foliose lettuce cactus coral Pavona cactus by cutting fronds and gluing them, with its spawning biology, asexual spread, and IUCN status.

Overview

Pavona cactus is a foliose stony coral of the family Agariciidae. Its colonies have vertical, irregular, two-sided fronds about 5 cm tall and can spread into supercolonies extending meters across the seabed. It is a zooxanthellate species, with symbiotic microscopic algae living in its tissues that convert sunlight into carbohydrates, supplying the coral with surplus nutrients.

Reproductive Mode

Pavona cactus reproduces both sexually and asexually. Gametes are released into the sea where fertilisation takes place; the egg hatches into a free-swimming planula larva that settles on the seabed and buds into a colony. Asexually, a bit of coral that has broken off a parent colony and become wedged in a suitable position can continue to grow and reproduce by budding to form a new colony.

Fragging / Asexual Propagation

The thin upright fronds make this one of the easier Pavona to frag. Cut a frond or section of plate from the colony, then mount it on a frag plug or rock. Dry the base of the cutting and the plug, add a couple of dabs of cyanoacrylate glue, secure the piece upright, and return it to low flow to cure. The frag heals and resumes producing new fronds.

Conditions for Propagation

A cactus frag needs stable reef chemistry, moderate to high light, and good flow around its fronds to keep detritus from collecting between the plates. Because the species relies heavily on its symbiotic algae, ample light drives the fast recovery and growth typical of this Pavona.

Common Challenges

Detritus and algae can lodge in the contorted fronds of a fresh frag, so maintain turbulent flow and inspect the plates. Pavona cactus is listed as Vulnerable on the IUCN Red List, with collection for the aquarium trade among its threats, which makes captive fragging a useful way to reduce pressure on wild colonies.