Acropora yongei (Green Slimer) Propagation Guide
Fragging and propagation of Acropora yongei, the fast-growing 'Green Slimer' small-polyp stony coral, increased readily by branch-tip cuttings in the reef aquarium.
Overview
Acropora yongei, widely known in the hobby as the "Green Slimer", is a small-polyp stony coral of the family Acroporidae and is listed by WoRMS as an accepted species (Veron & Wallace, 1984). It is a bright-green branching Acropora often suggested as an entry SPS because of its hardiness and fast growth. Like other Acropora it is a zooxanthellate coral whose tissues host symbiotic dinoflagellates that feed it through photosynthesis.
Reproductive Mode
Acropora reproduce both asexually and sexually. In the aquarium A. yongei is multiplied by fragmentation, which preserves the parent's symbiotic zooxanthellae and green coloration. Wikipedia notes that captive propagation of Acropora is widespread in the reef-keeping community.
Fragging / Asexual Propagation
Cut or snap a branch tip of about 2-5 cm with bone-cutters and bond it to a frag plug with cyanoacrylate gel or epoxy. The axial corallite at the branch tip drives regrowth, so an intact tip encrusts and elongates fastest. Wikipedia reports finger-sized Acropora fragments can grow into medicine-ball-sized colonies in one to two years; this fast-growing species responds especially quickly.
Conditions for Propagation
Wikipedia states Acropora requires bright light, stable temperatures, regular calcium and alkalinity dosing, and clean turbulent water. Place yongei frags under high light and strong flow with stable alkalinity, calcium and magnesium and low nutrients to support its rapid encrustation and branching.
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 event is generally not reproduced in home aquaria, where propagation relies on fragmentation.