Red-eye puffer
Carinotetraodon lorteti
A small freshwater puffer among the most fascinating and challenging in fishkeeping. Intelligent and personable, with mobile red eyes that follow the observer, its compact body changes color and pattern depending on mood and sex. Males display dorsal and ventral crests during courtship. Native to Southeast Asia (Thailand, Vietnam, Cambodia), it is strictly freshwater — no salt needed. A strict carnivore requiring hard-shelled snails to maintain its beak. Highly territorial and nippy: species-only tank mandatory in nearly all cases.
Water Temperature
24 - 28 °C
pH Value
6.5 - 7.5
Water type
Freshwater
Tank level
Bottom and middle
Adult size
6 cm
Minimum tank volume
>= 75 L
Minimum group
>= 1
GH
4 - 15 dGH
KH
2 - 7 dKH
TDS
80 - 295 ppm
Conductivity
125 - 461 uS/cm
Species description
Geographical Origin and Habitat: 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.
Care, breeding and tankmates
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 Cohabitation: 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 Breeding: 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.
Geographic Origin and Distribution
Native to mainland Southeast Asia (Thailand, Cambodia, Vietnam). Lives in shaded canals, slow-flowing rivers and densely vegetated freshwater swamps.
Origin
South and Southeast AsiaEast Asia
Fish profile
- Temperament
- Aggressive
- They are notoriously grumpy and aggressive. They actively predate on anything small. They possess a fierce but fascinating personality.
- Diet
- Carnivore
- Crunchy foods keep their teeth filed. Snails and small crustaceans are essential. Frozen bloodworms make good supplementary treats.
- Life expectancy
- 5-8 years
- In the aquarium, this freshwater pufferfish has an average lifespan ranging from 5 to 8 years when kept under optimal conditions. To ensure maximum longevity, it is necessary to avoid sharp variations in pH and water hardness. Careful attention to skin infections, to which it is prone, contributes significantly to its survival.
- Adult size
- 6 cm
- The catalog's scalar value is 6 cm. The FishBase SPECIES table (v25.04 snapshot) source reports a maximum adult measurement of 6 cm for this species, recorded as standard length (SL). The taxonomic record consulted is Carinotetraodon lorteti (v25.04); male or unsexed record. These figures are not interchangeable: the first is the profile's editorial reference, whereas the second is a published maximum under a specific measurement convention; differences among sources can reflect sex, population, life stage and measuring method.
- Sex ratio
- Harem
- Managing the sex ratio is critically important for Carinotetraodon lorteti due to the highly aggressive and territorial nature of the males. It is highly recommended to keep them either as single specimens or in a harem arrangement containing one male to several females (at least 2-3 females per male). Housing multiple males in the same aquarium almost inevitably leads to fierce, often fatal, combat as they mature and assert dominance. Even within a proper harem structure, providing abundant visual barriers and hiding spots is essential to diffuse any intraspecific tension.
- Feeding frequency
- Twice daily
- Once a day is generally sufficient. Avoid letting their bellies bulge excessively. Skipping a day mimics natural habits.
- Bioload
- Low to Medium
- They create a surprisingly high bioload. Messy eating habits foul water quickly. Excellent biological filtration is strictly required.
- Flow
- Strong
- They inhabit sluggish, calm natural waters. Slow to moderate flow is preferred. Strong currents cause them massive stress.
- Jump risk
- No
- Reproduction
- Oviparous
- Captive breeding is extremely difficult to achieve. Males become fiercely territorial during spawning. Eggs are scattered without parental care.
- Compatibility & tankmates
- Community
- They are fiercely aggressive fin-nippers. Species-only tanks are highly recommended. Tank mates are usually severely injured.
- Tank level
- Middle/Bottom
- Redeye puffers are predominantly bottom-to-middle dwelling fish that intricately associate themselves with the hardscape and flora of the aquarium. They can often be seen hovering just above the substrate or navigating methodically through dense thickets of aquatic plants. They rarely venture into the open upper levels of the water column unless actively pursuing food or moving to a new territory. Providing a complex environment in the lower half of the tank with driftwood, leaf litter, and caves is crucial for their behavioral enrichment.
Scientific Parameters & Models
FishBase
Window to the official scientific data of the species
Data synced on: 06/15/2026
- Trophic level
- 3.5 ± 0.46 se
- Resilience
- High (less than 15 months)
- Phylogenetic uniqueness (PD50)
- 0.5156
- Bayesian Length-Weight
- a = 0.0263, b = 2.88
- VulnerabilityLow vulnerability (10 / 100)
Image gallery
Licensed images linked to the species or, when marked, to the closest representative taxon.
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