Holy Grail Torch (Euphyllia glabrescens) Propagation Guide

How to propagate the Holy Grail morph of Euphyllia glabrescens (torch coral): fragging the phaceloid skeleton between heads, managing sweeper-tentacle aggression and brown-jelly risk.

Overview

The Holy Grail is a sought-after color morph of Euphyllia glabrescens, the torch coral, a large-polyped stony coral in the family Euphylliidae. Euphyllia glabrescens forms colonies with a phaceloid skeleton, where tubular corallites roughly 20-30 mm in diameter sit on separate branches spaced 15-30 mm apart. This branching skeletal structure is what makes torch corals amenable to fragging.

Reproductive Mode

In the aquarium, Euphyllia glabrescens is propagated asexually by fragmentation. Because each polyp head grows on its own length of tubular skeleton, a colony can be divided into individual heads that each regrow into a new colony over time. Reef Builders describes torch corals as relatively easy to frag thanks to this distinct branching skeleton, with single heads removed and grown out to repeat the cycle.

Fragging / Asexual Propagation

1. Identify the gaps in the skeleton between corallite heads; plan cuts so each frag keeps a length of its own skeleton.
2. Cut through the bare skeleton between heads with coral cutters or a band saw, which gives a cleaner flat edge.
3. Avoid cutting through the fleshy polyp tissue itself; work between the heads.
4. Dip the new frags in a coral dip to remove pests, as is done when reshaping a Holy Grail torch colony.
5. Glue or epoxy each frag to a plug and place it in low flow and moderate light until the tissue recedes from the cut and heals.

A torch colony can be grown from a single corallite into roughly a dozen polyps over about two years, after which it can be fragged again.

Conditions for Propagation

Stable parameters speed recovery: temperature near 24-26 degrees Celsius, pH 8.1-8.4, and alkalinity, calcium, and magnesium kept steady so the skeleton can extend. Moderate flow and medium light help the frag heal without irritating the freshly cut tissue.

Sexual Reproduction

Sexual reproduction in Euphyllia occurs on the reef rather than in home aquaria and does not contribute to hobby propagation. Detailed gamete data for E. glabrescens is not documented in the consulted sources, so only asexual fragmentation is used by aquarists.

Common Challenges

Torch corals carry long sweeper tentacles tipped with potent cnidocytes that can sting neighbouring corals, so frags need open space. The freshly cut tissue is also vulnerable to brown jelly, a contagious ciliate infection that can spread between corallites and jump to other Euphyllia within days; affected tissue should be fragged off and discarded.