Common name: Anchor coral

General information

The Hammer Coral, scientifically known as Euphyllia ancora, is a popular large polyp stony (LPS) coral in the reefkeeping hobby. It is prized for its unique hammer- or anchor-shaped tentacles, which can come in a variety of colors, including green, brown, purple, and even gold. These corals are not only visually striking but also exhibit interesting behaviors and are relatively hardy, making them a favorite among aquarists.

Care

Hammer Corals require moderate to high lighting and moderate water flow within the aquarium to thrive. They benefit from stable water conditions and the presence of calcium, alkalinity, and magnesium to support their skeletal growth. It's important to provide ample space between Hammer Corals and other species, as they can be aggressive and have sweeper tentacles that can harm neighboring corals.

Feeding is not strictly necessary as they host zooxanthellae algae that provide them with nutrients through photosynthesis. However, supplemental feeding with meaty foods can promote growth and vitality.

Symbiosis

While Hammer Corals do not have a symbiotic relationship with fish like clownfish-anemone pairings, they can provide shelter to a variety of small reef creatures. Some aquarists have observed small fish and crustaceans seeking refuge among the coral's tentacles.

Habitat

Euphyllia ancora is found in the Indo-Pacific region, typically in reef environments with moderate to strong water currents. They are often located at depths where light is sufficient for their symbiotic algae to photosynthesize effectively.