Longhorn Cowfish EXPERT ONLY

Overview

Key Characteristics

• Appearance: It has a hard, box-like carapace made of fused, hexagonal scales, with fins and a tail protruding from the rigid structure. It typically has a yellow to olive base color decorated with white or bluish spots.
• Horns: It is named for the two long horns on its head and another pair of spines extending from the rear of its body. These are thought to make the fish harder for predators to swallow.
• Size: In the wild, longhorn cowfish can grow up to 20 inches (50 cm) in length, though they are usually smaller in aquariums.
• Swimming: It uses a unique method called “ostraciiform” locomotion, where it primarily moves using its dorsal and anal fins, giving it a hovering appearance.
• Defense: The fish’s skin is poisonous. When severely stressed or threatened, it can release a potent neurotoxin, ostracitoxin (or pahutoxin), into the water, which can be lethal to other fish in a confined space, including itself. 

Habitat and Diet

• Habitat: The longhorn cowfish primarily lives in coral reef lagoons, on reef flats, and in protected areas with sandy or rubble bottoms in the tropical Indo-Pacific. Juveniles often hide among Acropora corals.
• Diet: It is an omnivore, feeding on benthic algae, microorganisms, sponges, polychaete worms, mollusks, and small crustaceans. It locates buried prey by blowing jets of water into the sand. 

Aquarium Care

• Tank Requirements: A large aquarium (minimum 180-250 gallons for an adult) is recommended, with plenty of open swimming space and a sandy substrate to allow for natural feeding behaviors. Low to moderate water flow is preferred.
• Tank Mates: They are generally peaceful but should not be housed with aggressive or fast-moving fish that may stress them or outcompete them for food. They are not considered strictly reef-safe as they may nibble on tubeworms and other small invertebrates.
• Feeding: A varied diet of high-quality meaty foods (e.g., mysis shrimp, chopped clams) and algae-based preparations is necessary.
• Handling: Traditional mesh nets should be avoided to prevent their horns from getting snagged and to minimize stress. Coaxing them into a plastic container is a safer method. 

Approximate Purchase Size: Small: 1″ to 2″; Medium: 2″ to 3; Large: 3″ to 5″