Hammerhead Branched Hard Coral Euphyllia Sp

Description

Hammerhead Branched Hard Coral (Euphyllia sp.)

(Also known as Hammer Coral, Anchor Coral, or Branching Hammer Coral)

Overview

The Hammerhead Branched Hard Coral (Euphyllia sp.) is one of the most recognisable and admired large-polyp stony (LPS) corals, famed for its distinct hammer- or anchor-shaped tentacles and gentle, flowing movement. With colours ranging from fluorescent green and gold to purple, pink, and bicolour varieties, it adds vivid motion and texture to reef aquariums. The branching growth form makes it ideal for propagation and aquascaping, and its hardy nature has made it a staple coral for both intermediate and experienced reef keepers.

Origin

Native to the Indo-Pacific region, including the Coral Sea, Great Barrier Reef, Fiji, Tonga, Indonesia, and the Solomon Islands. Found on protected reef slopes and lagoons, where light and current are moderate.

Feeding

The Hammer Coral is photosynthetic, hosting symbiotic zooxanthellae that supply most of its nutrition. Nonetheless, regular supplemental feeding encourages growth and vibrant colouration. Feed 1–2 times per week with:

• Mysis shrimp or enriched brine shrimp

• LPS coral foods and marine plankton blends

• Finely chopped seafood (optional)

Target feeding is most effective when flow is reduced, allowing tentacles to capture food easily.

Lighting

Moderate lighting. Provide strong but diffused light from LED, T5, or metal halide fixtures.

• PAR range: 100‚Äì200 ¬µmol/m¬≤/s

• Avoid intense, direct lighting that can cause tissue retraction or bleaching.

• Blue-spectrum lighting enhances the coral‚Äôs fluorescent tones and gives it a vibrant glow.

Water Flow

Low to moderate, indirect flow. Gentle, alternating currents are ideal, creating a natural swaying motion without tearing or stressing the delicate polyps. Avoid direct or turbulent flow that may cause tissue damage.

Placement

• Position on lower to mid-level rockwork or the substrate, in areas with moderate light and flow.

• Allow at least 10‚Äì15 cm (4‚Äì6 inches) clearance from other corals ‚Äî Euphyllia species possess long sweeper tentacles capable of stinging nearby colonies.

• Ensure rockwork is stable to prevent damage when polyps are fully extended.

Tank Mates

Reef safe with caution. Compatible with:

• Peaceful reef fish (clownfish, tangs, gobies, wrasses, etc.)

• Invertebrates (snails, hermit crabs, shrimp)

• Other Euphyllia species (hammer, frogspawn, torch) ‚Äî sometimes cohabitable if from the same genetic group

Avoid:

• Aggressive corals (e.g., Galaxea, Hydnophora, Torch corals from other colonies)

• Large angelfish, butterflyfish, or puffers that may nip tentacles

Aggression

Moderately aggressive. Extends sweeper tentacles (up to 7 cm / 3 in) at night to defend its space. Maintain adequate spacing and moderate water flow to prevent contact with other corals.

Experience Level

Intermediate. Euphyllia species are hardy but sensitive to rapid parameter changes. Consistent lighting, stable chemistry, and gentle flow are key to long-term success.

Water Parameters

• Temperature: 24‚Äì27¬∞C (75‚Äì81¬∞F)

• pH: 8.1‚Äì8.4

• Salinity: 1.024‚Äì1.026 SG

• Alkalinity: 8‚Äì12 dKH

• Calcium: 400‚Äì450 ppm

• Magnesium: 1250‚Äì1350 ppm

• Nitrate: <10 ppm

• Phosphate: <0.03 ppm

• Tank Size: Minimum 100 litres (25 gallons); larger systems recommended for colonies

Stable calcium and alkalinity levels support strong skeletal growth and healthy polyp expansion.

Reef Compatibility

Reef safe with caution. The Hammerhead Branched Coral makes a spectacular centrepiece for mixed reef systems. Its movement adds life and dynamism to aquascapes, while its branching structure allows for easy fragging and propagation. Given space and stable conditions, it will thrive for years as one of the reef’s focal points.

Interesting Fact

The name “Hammer Coral” comes from the coral’s unique polyp tips, which resemble the curved head of a hammer or anchor. This structure increases surface area for photosynthesis and enhances its hypnotic swaying motion in the current.