Foxface Rabbitfish

Geographic Origin and Biotope: Western Pacific Ocean. Frequents reefs rich in branching corals (Acropora) and sheltered lagoon reefs, where it tirelessly grazes the algal cover on the rocks.

Taxonomy and Morphology: Foxface Rabbitfish (Siganus vulpinus). It has an elongated and tubular snout to slip between the corals to tear off algae. The rays of the dorsal and anal fins hide retractable venomous spines.

Social Behavior: Shy but armored. Juveniles live in pairs or small groups, adults are mostly solitary. If frightened, it erects all its spines in a fan and retreats into a corner, becoming an impenetrable "stinging wall" for predators.

Coloration and Sexual Dimorphism: Yellow and Black Warning. The body is a dazzling golden yellow, with a prominent black and white spot/band on the snout that resembles a mask (fox face). When it sleeps or is stressed, it "turns off" the yellow becoming horribly mottled with military brown/gray.

Aquarium Setup: Large marine aquarium (Minimum 120 cm / 48 inches). Lots of well-established live rocks with crevices where it can hide during the night. Avoid overly frantic or aggressive tankmates who would corner it.

Diet and Feeding: Grazing herbivore. Devours the annoying bubble algae (Valonia) and tuft algae, making it very useful. In addition to spontaneous algae, it must be fed heavily with Nori seaweed sheets (fixed to a clip) and vegetable feeds.

Water Quality: Clean and well-oxygenated marine water. It is very robust and resistant to the most common skin diseases compared to surgeonfish, but does not tolerate high nitrate accumulations typical of neglected tanks.

Compatibility and Tankmates: Reef Safe "with caution". If well fed, it ignores corals. If hungry, it will mercilessly nip the polyps of soft corals (LPS) and giant clams. Excellent with peaceful fish; aggressive fish avoid attacking it because of its lethal spines.

Aquarium Reproduction: Never documented in amateur aquariums. They reproduce in nature by releasing clouds of pelagic eggs at sunset.

Risks and Diseases: The Venomous Sting. The dorsal, pelvic and anal spines are connected to venom glands. Accidental stinging during maintenance causes excruciating pain similar to a scorpion sting (to be treated by immersing the part in very hot water to denature the proteins).