Red-eye puffer

Geographic Origin and Biotope: Native to mainland Southeast Asia (Thailand, Cambodia, Vietnam). Lives in shaded canals, slow-flowing rivers and densely vegetated freshwater swamps.

Taxonomy and Morphology: Red-eye Puffer (Carinotetraodon lorteti). Freshwater puffer fish, reaches about 6 cm (2.4 inches). Characterized by an erectile dorsal or abdominal bony "keel" and, obviously, the ability to puff up.

Social Behavior: Extremely aggressive, unpredictable and territorial. Spends a lot of time hidden among the leaves, waiting for prey. Keeping them in groups (even among conspecifics) in small tanks is strongly discouraged.

Coloration and Sexual Dimorphism: Highly accentuated dimorphism. Males: bright red eye, red belly, greenish/brownish back with no pattern. Females: white belly, light eye, brownish body with complex reticulated "cobweb" pattern.

Aquarium Setup: 60-80 cm (24-32 inches) tank for a single male or a small harem (1 male and 2-3 females) full of roots and dense plants to break visual lines. The bottom must be inert sand to allow them to partially bury themselves.

Diet and Feeding: Specialized carnivore. Live snails are vital for filing the tooth beak that grows continuously. Accepts bloodworms, frozen shrimp and krill. Categorically refuses dry feeds.

Water Quality: It is a *strictly freshwater* puffer fish, it does not need salt. Intolerant of nitrate accumulations (sensitive to dirty water bacteria) and violent water changes.

Compatibility and Tankmates: Relentless fin nipper. Must be kept alone. If paired with other fish (even armored ones like Corydoras), it will systematically remove eyes and fins during the night with pincer-like bites.

Aquarium Reproduction: Difficult. The male chooses a site (often Java moss), attracts the female for a brief spawning and then violently drives her away, solitarily taking on parental care of the eggs (which he ventilates with his fins).

Risks and Diseases: In addition to hypertrophy of the beak (lethal if not worn down with snail shells), it is exposed to internal poisons. If exposed to the air, it ingests oxygen by puffing up and can no longer expel it, dying of asphyxiation. Never take it out of the water.