TankBud

Figure eight puffer

Tetraodon biocellatus

FreshwaterBrackishFish

Figure eight puffer (Tetraodon biocellatus)
Robin Geyer · Public domain

Care at a glance

Temperature
72–79°F
22–26°C
pH
6.5–7.5
Adult size
3.1 in
8 cm
Minimum tank
20 gal
75 L
Temperament
Mostly peaceful
Social behavior
Social
Tankmates
With caution
Swim level
Middle
Difficulty
Medium
Breeding
No record
Rarity
Rare
Family
Tetraodontidae
Origin
Cambodia, Malaysia, Borneo

Overview

The figure eight puffer is one of the more even-tempered brackish puffers, though it can still nip, so treat it as a species-tank fish. It can sometimes be kept in a small group or with fast, salt-tolerant tankmates in a larger tank, but always watch for fin-nipping and be ready to separate troublemakers. Give it hiding spots among wood and plants that tolerate a little salt. Its teeth grow continuously, so feed hard-shelled foods such as snails and small shellfish along with frozen bloodworms and shrimp. A single fish is comfortable in a tank of around 75 liters, with more room needed for a group.

In the wild

This little puffer comes from the lower rivers, estuaries, and floodplains of Cambodia, Malaysia, and Borneo, where it lives mostly in fresh water that turns slightly brackish near the coast. It does well in hard, alkaline fresh water or lightly brackish conditions, so many keepers add a small amount of marine salt. Keep the pH between 6.5 and 7.5 and the temperature from 22 to 26 C. Provide gentle flow, a soft substrate, driftwood, and some robust or salt-tolerant plants for cover, along with clean, stable water.

Good to know

The figure eight puffer is a member of the family Tetraodontidae and is now formally placed in the genus Dichotomyctere, as Dichotomyctere ocellatus, though the older name Tetraodon biocellatus is still widely used in the trade. Adults stay small at about 8 cm and carry a dark, looping pattern on the back that can resemble a figure eight. Like all true puffers it has fused, beak-like teeth and can inflate with water when startled. Aquarium breeding is not established, and fish in shops are wild caught.

Did you know

The figure eight puffer gets its name from the looping golden and dark markings on its back, which on many fish trace out a shape like the number eight. Each fish carries its own version of the pattern, so no two are marked in quite the same way.

Common questions

What size tank does a Figure eight puffer need?

A Figure eight puffer needs at least 20 gal (75 L). It spends most of its time in the middle.

What temperature and pH does a Figure eight puffer need?

A Figure eight puffer is comfortable at 72–79°F (22–26°C) with a pH of 6.5–7.5.

How big does a Figure eight puffer get?

An adult Figure eight puffer reaches about 3.1 in (8 cm).

Related species