Propagating Hawaiian Sunset Montipora digitata

Fragging the Hawaiian Sunset color morph of the branching coral Montipora digitata, family Acroporidae: branch cuttings, spawning biology, and the Phestilla nudibranch pest.

Overview

Hawaiian Sunset is an aquarium color morph of Montipora digitata, a branching coral in the family Acroporidae. According to Wikipedia, the species grows as digitate or bushy mounds of vertically aligned, anastomosing branches reaching over 40 centimetres across, with small, deeply embedded corallites. The morph denotes coloration only and is propagated exactly like the base species.

Reproductive Mode

M. digitata is a simultaneous hermaphrodite that spawns annually, releasing gamete packets that float upward for cross-fertilisation among colonies. As a zooxanthellate coral, its symbiotic dinoflagellates supply up to 90 percent of its energy, with planktonic prey making up the difference. In aquaria the Hawaiian Sunset morph is maintained through fragmentation, not spawning.

Fragging / Asexual Propagation

Propagation follows standard digitate technique: a finger branch is snapped or clipped from the parent and glued to a plug or rock, then grown under medium-high light and flow to form a fresh bushy colony. Keeping intact growing tips on the cuttings helps the orange branches and blue polyps of the morph color up as the frag matures.

1. Clip a 2-4 cm finger branch with a clean growing tip.
2. Glue it upright onto a plug with reef-safe adhesive.
3. Provide stable medium-high light and water movement.
4. Allow the base to encrust before moving the frag.

Common Challenges

The Montipora-eating nudibranch poses the same danger to this morph as to any Montipora. Phestilla subodiosus feeds specifically on the genus and causes significant losses in aquacultured stock. Because its eggs hide in branch crevices, fragments that look clean can still carry the pest into a tank.