Description
Purple Bush Gorgonia (Briareum asbestinum)
(Also known as the Corky Sea Finger, Purple Bush Coral, or Encrusting Gorgonian)
Overview
The Purple Bush Gorgonia (Briareum asbestinum) is a hardy, fast-growing, photosynthetic soft coral that forms bushy, finger-like branches with a distinctive purple or violet base and bright green or cream-coloured polyps. It is closely related to the popular Green Star Polyp (Briareum sp.) and is equally resilient, making it an excellent choice for both beginner and experienced reef aquarists. This coral adds vibrant movement and texture to aquariums and can quickly encrust nearby rockwork, creating a lush, living mat of polyps.
Origin
Found throughout the Caribbean Sea and Western Atlantic, including the Florida Keys, Bahamas, and Gulf of Mexico. Commonly inhabits shallow reef slopes and hard substrates exposed to moderate water flow and strong light.
Feeding
The Purple Bush Gorgonia is photosynthetic, hosting symbiotic zooxanthellae that provide most of its nutrition through photosynthesis. While not dependent on direct feeding, it benefits from occasional supplemental nutrition to enhance growth and colour:
-
Phytoplankton or microplankton (1–2 times per week)
-
Marine snow or coral-specific powdered foods
-
Occasional amino acid or trace element supplements
Polyps passively capture fine particulate food from the water column, but excessive feeding is unnecessary.
Lighting
Moderate to high lighting. Strong illumination from LED, T5, or metal halide systems supports both zooxanthellae and vibrant colouration. PAR levels between 150–250 µmol/m²/s are ideal. Too little light can cause fading and reduced growth.
Water Flow
Moderate to strong, indirect flow. Consistent water movement helps keep the polyps extended, removes detritus, and delivers nutrients. Avoid direct jets that could damage tissue or prevent polyp extension.
Placement
-
Mount on rockwork in the mid to upper regions of the aquarium.
-
Allow ample space — Briareum asbestinum spreads quickly and can overgrow nearby corals.
-
Ideal for rock walls, overhangs, or isolated islands to control growth.
Tank Mates
Peaceful and reef safe. Compatible with:
-
All reef-safe fish (clownfish, gobies, blennies, tangs, etc.)
-
Cleaner shrimp, snails, hermits, and other invertebrates
-
Most soft and LPS corals (with adequate spacing)
Avoid:
-
Large angelfish and butterflyfish that may nip at polyps
-
Corals sensitive to allelopathic competition (e.g. leathers, mushrooms) when placed too close
Aggression
Mildly aggressive. While not stinging, Briareum can outcompete or overgrow nearby corals through rapid mat-like expansion. Regular pruning and spacing help maintain control. Use activated carbon filtration to reduce chemical competition in mixed reefs.
Experience Level
Beginner to intermediate. One of the hardiest and fastest-growing gorgonians, ideal for aquarists looking to add movement, colour, and structural height to their reef tank without complex feeding requirements.
Water Parameters
-
Temperature: 24–27°C (75–81°F)
-
pH: 8.1–8.4
-
Salinity: 1.024–1.026 SG
-
Hardness (dKH): 8–12
-
Calcium: 400–450 ppm
-
Nitrate: <10 ppm
-
Tank Size: Minimum 50 gallons (190L) recommended for stability and growth space
Maintain stable water chemistry, consistent light, and moderate nutrient levels for healthy growth and vibrant colour.
Reef Compatibility
Fully reef safe. Briareum asbestinum adds motion, colour, and vertical interest to mixed reef aquariums. Its photosynthetic nature and tolerance of varying conditions make it suitable for a wide range of setups, though its rapid growth requires occasional trimming.
