Rainbow Favia (Dipsastraea sp.): Propagation Guide

Propagating the designer Rainbow Favia (Dipsastraea), a plocoid brain coral, by sawing the colony so each frag keeps separate-walled corallites, plus spawning notes.

Overview

The aquarium 'Favia' brain corals of the Indo-Pacific now belong to the genus Dipsastraea in the family Merulinidae, established by Blainville in 1830 and absorbing several former genera. These are zooxanthellate corals native to the Indo-Pacific. The 'Rainbow' designation refers to high-color morphs prized for the concentric rings around each corallite.

Reproductive Mode

Dipsastraea are reef-building stony corals carrying symbiotic zooxanthellae in their tissues. As with most reef-building corals, sexual reproduction is by gamete release into the water; in the aquarium the practical method is asexual division of the colony. Each polyp sits in its own corallite, which makes the colony straightforward to cut between heads.

Fragging / Asexual Propagation

Because each polyp has a separate corallite wall, the colony is fragged by cutting between the heads so every frag keeps one or more complete, undamaged corallites with live tissue. A band saw gives the cleanest cut on the dense skeleton; cut frags are dipped, dried, glued to plugs, and returned to gentle conditions to heal.

Conditions for Propagation

Healing frags do best under the parent's preferred medium light and moderate flow strong enough to keep detritus off the cut surface but gentle enough that the polyps stay open. Stable alkalinity and calcium support re-encrustation over the exposed skeleton.

Common Challenges

Exposed cut edges can be invaded by algae or recede if conditions swing, so a clean cut and a coral dip reduce infection risk. Designer color morphs may pale under unstable lighting, and brain corals generally re-cover sawn skeleton slowly.