The Figure Eight Puffer (Tetraodon biocellatus) is also known as the Eye Spot Puffer and is found in the rivers and coastal waters of Cambodia, Malaysia, Borneo, and Indonesia.
The Figure Eight Puffer is a colorful little fish that is dark brown to green on the back with a white belly. It has greenish yellow patterns and spots on their backside that vary from specimen to specimen. A few black spots are outlined in yellow on the tail, body and nose, and the marking on either side of their caudal fins resemble the number 8, or an “eye spot”, which probably contributes to their name. It is virtually impossible to sex Figure Eight Puffers, but females are thought to grow larger than the males.
Although the Figure Eight Puffer is most often found in freshwater, they also frequent brackish waters in coastal areas.
Most Figure Eight Puffers are relatively peaceful compared to other puffer fish. In freshwater, they can be kept with fast moving species like characins, rasboras, mollies and barbs. They will nip the fins of slow moving fish.
In a brackish water environment, they do well with barbs, bumblebee gobies, Monos, mollies, salt tolerant Chanda species, etc.
Figure Eight Puffers should be housed in a heavily filtered 15 to 20 gallon aquarium. Like all puffer fish they are sensitive to nitrates, nitrites and ammonia and because they are such sloppy eaters, heavy filtration and frequent water changes are mandatory.
Figure Eight Puffers are a long lived, active species that need plenty of room for swimming when they are not hiding. These puffers are best kept in a densely planted tank with lots of twisted driftwood roots for cover, and a sandy substrate. A few floating plants should also be included to diffuse light in their tank.
Figure Eight Puffers are classed as molluscivores. They will readily feed on mussels, oysters, cockles, krill, shrimp, earthworms and snails. Some puffers can be trained to take other foods, such as flake food or pellets, but it should not be their primary diet. Live snails are recommended to keep their fused teeth from becoming overgrown.
Although the Figure Eight Puffer is considered a true freshwater species, it tends to live longer with the addition of marine salt to their aquariums.
Spawning occurs in brackish water where the eggs are laid on the bottom substrate or on flat rocks. After the eggs are fertilized, the male will guard them for approximately a week until the fry become free swimming.
Although not as common as its counterpart Tetraodon ocellatus, when available for purchase they are generally about 3/4″ to 1 1/2″ in size.
Minimum Tank Size: 20 gallons
Care Level: Moderate
Temperament: Aggressive
Aquarium Hardiness: Moderately Hardy
Water Conditions: 72-82° F, kH 8-15, pH 6.5-7.5
Max. Size: 3.5″
Color Form: Green, Tan, White, Yellow
Diet: Molluscivore
Origin: Southeast Asia, Borneo
Family: Tetraodontidae
Lifespan: Up to 15 years
Aquarist Experience Level: Intermediate