Galaxy Coral Care Guide

Galaxy Coral (Galaxea fascicularis) is a LPS coral. Care covers 75-175 PAR, medium flow, reef parameters and feeding; intermediate level.

Overview

Galaxy Coral (Galaxea fascicularis) is a LPS coral in the family Euphylliidae. Spectacular LPS with star-burst polyps and very long, very aggressive sweeper tentacles. Place isolated to avoid burning neighbors.

Taxonomy

Family: Euphylliidae
Genus: Galaxea
Scientific name: Galaxea fascicularis
Common synonyms: Crystal Coral, Star Coral

Habitat

In the wild, Galaxea fascicularis is reported from Indo-Pacific, where it occupies mid to lower reef slopes and lagoons (typically 5-30 m). The species adopts a branching growth form on hard substrate within zooxanthellate reef communities.

Tank requirements

Salinity (specific gravity): 1.024-1.026
Temperature: 24-26 °C (75-79 °F)
pH: 8.1-8.4
Carbonate hardness (dKH): 8-11
Calcium: 400-450 ppm
Magnesium: 1280-1350 ppm
Phosphate (max): 0.03 ppm
Nitrate (max): 5 ppm
Minimum system age: 6 months

Placement and lighting

PAR (placement zone): 75-175 PAR
Water flow: medium

Mount this LPS coral on the lower or mid rockwork or on the sand bed (for free-living forms) where light is moderate. Strong direct flow can damage the fleshy tissue; aim for indirect, varied movement.

Feeding

Galaxea fascicularis hosts symbiotic zooxanthellae and derives most of its energy through photosynthesis. Supplemental target feeding accelerates growth and supports colouration; commonly accepted items include mysis, reef-roids. Feed once or twice per week after lights-out, when polyps are extended.

Compatibility

This coral is very-aggressive toward neighbours. It extends sweeper tentacles capable of stinging adjacent corals, so leave generous spacing (10-20 cm) between colonies. Reef-safe with most fish and invertebrates.

Care notes

Difficulty level: intermediate. Reported skeletal growth in well-tuned reef tanks is approximately 0.2-0.5 cm/month. Propagation by fragmentation is straightforward for branching colonies — separate branches or polyps with a bone cutter, glue to plug, allow 1-2 weeks for healing. Maintain stable alkalinity (avoid swings above ±0.5 dKH per day) to preserve tissue health.