Figure 8 Puffer ~ Tetraodon biocellatus

The Figure 8 Puffer is a small, colorful brackish-water fish known for its playful personality and distinct patterns resembling the number eight on its back. Native to slow-moving rivers and coastal areas of Southeast Asia, this semi-aggressive species is best suited for aquarists with experience maintaining stable water conditions and providing a species-specific setup.

• Size: 2-3 inches
• Lifespan: 8-10 years
• Temperament: Semi-aggressive, territorial
• Group/Solitary: Best kept singly or in a small group in a spacious tank
• Food: Carnivorous; live/frozen foods (snails, shrimp, bloodworms, mussels)
• Water Requirements: 75-82°F, pH 7.5-8.5, brackish water (specific gravity: 1.005-1.008)

Figure 8 Puffers are native to brackish environments such as tidal estuaries and mangrove swamps, where they feed on invertebrates. In aquariums, they require a brackish setup with a specific gravity of 1.005-1.008, achieved by mixing marine salt with freshwater. A tank of at least 20 gallons is recommended for a single puffer, with an additional 10 gallons per puffer if kept in a group. They thrive in a setup with a sandy substrate, smooth rocks, driftwood, and plants tolerant of brackish conditions, such as Java Fern and Anubias.

As carnivores, Figure 8 Puffers require a diet rich in live or frozen foods, such as snails, mussels, shrimp, and bloodworms. Hard-shelled foods like snails are essential for preventing overgrowth of their continuously growing teeth. They should be fed small amounts several times a day to maintain their health and activity.

While generally less aggressive than other puffer species, Figure 8 Puffers are still territorial and may nip at tankmates. They are best kept in species-specific tanks or with fast, robust fish that can tolerate brackish water, though even then, caution is advised. Provide plenty of hiding spots and visual barriers to reduce stress and aggression.

Fun Fact: Figure 8 Puffers are known for their intelligence and curiosity. They can recognize their owners, often following them along the glass or "begging" for food, making them one of the most interactive fish in the aquarium hobby.