Longhorn Cowfish EXPERT (Lactoria Cornuta)

Longhorn Cowfish Also Known As: Longhorn Boxfish, Horned Cowfish

Compatibility and Behavior
The Longhorn Cowfish is undoubtedly one of the most unique-looking fish in the entire hobby. The body is box-shaped and golden-yellow, scattered with pale blue to white spots, and topped off with a pair of long, forward-pointing horns above the eyes that give it that unmistakable cow-like profile. Note that these horns start off fairly short on small specimens, and will grow more prominent as they mature. This is a generally peaceful, slow-moving species that often does well alongside calm, non-aggressive tankmates that won't nip at its fins or beat it to the food. Like other boxfish and cowfish, it falls into the reef safe with caution category. Some individuals will pick at invertebrates or soft corals, and stress or harassment makes that behavior more likely. Settled into a quiet, stable community, a Longhorn Cowfish often becomes one of the most personable fish you'll ever keep, methodically inspecting the rockwork and coming up to the front glass to interact with its keeper.

Aquarium Requirements
A large, mature marine aquarium with a wide footprint is the right home for this species. Plan for ample open swimming space along with plenty of rockwork to explore at a relaxed pace. Gentle to moderate flow lets the fish maneuver comfortably without getting pushed around. Peaceful tankmates, stable water conditions, and patient acclimation all matter a lot here, since cowfish are sensitive to stress and to fluctuations in water quality. Aquascape with shaded areas, caves, and overhangs for retreat, while keeping open runways along the front of the tank where the fish can cruise and forage. Offer a varied diet of frozen mysis shrimp, finely chopped meaty marine foods, marine algae, and quality omnivore pellets to support both body condition and natural grazing behavior.

One important note on cowfish toxicity: like all Ostraciidae, the Longhorn Cowfish can release a potent toxin (ostracitoxin) when severely stressed or dying. In a closed aquarium, this can wipe out the entire tank, so it's worth having activated carbon and emergency water change supplies ready.

Specifications
Approximate Size: Sm: .75-1.5", Md: 2-3", Lg: 3-4"
Diet: Omnivore (frozen mysis shrimp, finely chopped meaty marine foods, marine algae, quality pellets)
Origin: Indo-Pacific 
Care Level: Expert (requires stable water conditions, peaceful tankmates, and careful feeding)
Reef Safe: With caution (may nip at some invertebrates or soft corals)
Temperament: Peaceful
Minimum Tank Size: 50 gallons for small specimen, 80+ gallons recommended
Special Considerations: Can release a tank-wiping toxin (ostracitoxin) when severely stressed or dying; sensitive to water quality and stress; best housed with peaceful, similarly paced tankmates