2 Head Rainbow Hologram HammerHammer Coral (Euphyllia ancora) Lighting Requirements: Moderate to High Water Flow: Medium Care Level: Moderate Placement: Middle to Lower Levels Temperament: Aggressive The Hammer Coral is a stunning and highly sought after species that will bring a unique touch to any reef aquarium. Named for its distinct, hammer shaped tentacles, this coral comes in a variety of vibrant colors, from greens and yellows to deep pinks and purples. Its an ideal choice