Figure 8 Puffer (Brackish)

Dichotomyctere ocellatus

Puffers

A small, highly intelligent, and interactive pufferfish known for the distinctive figure-eight pattern on its back. While often sold as freshwater fish, they strictly require a low-end brackish environment (Specific Gravity 1.005-1.008) for long-term health and a full lifespan. They are aggressive fin-nippers and strict carnivores that require hard-shelled foods (like snails) to keep their continuously growing teeth trimmed.

At a Glance

Adult Size8 cm
Body ShapeGlobular
Growth RateModerate
TemperamentAggressive
Water TypeBrackish Required
Flow PreferenceModerate
Waste OutputHigh
StockingSolo or group

Tank Requirements

Minimum Volume60 L
Minimum Length60 cm
FlowModerate
Water TypeBrackish Required
Must-Haves in the Tank
Sand (Sifters)Shells (Breeding/Hiding)

Water Parameters

Temperature2428°C
pH7.58.5
Hardness1025 dGH

Temperament & Compatibility

Aggression LevelAggressive
8/10
Where They Swim
Surface
Mid-level
Bottom
Stocking Guidelines
Keep at Least1 (solo is fine)
Max per TankNo limit
Can Live Alone?Yes
Behavior Traits
Snail EaterShrimp EaterFin NipperGenerally AggressiveTerritorial (Defends specific area)Hyperactive / Fast Swimmer

Available Varieties

Each variety inherits the species defaults above. Only differences are highlighted.

Standard

The standard Figure 8 puffer. Best kept singly or in a heavily decorated, species-specific brackish setup to manage extreme territorial aggression.

Differs in 1 trait from base species

Also known as: F8, Wild Type

Behavior Traits
Snail EaterShrimp EaterFin NipperGenerally AggressiveTerritorial (Defends specific area)Hyperactive / Fast Swimmer

Figure 8 Puffer (Brackish) Care Summary

The Figure 8 Puffer (Brackish), scientifically known as Dichotomyctere ocellatus, belongs to the Puffers family group. Adults reach a maximum size of approximately 8 cm and have a globular body shape with a moderate growth rate. Classified as aggressive, this species primarily occupies the mid-level and bottom zones of the aquarium and produces a high level of biological waste.

To thrive, the Figure 8 Puffer (Brackish) requires a brackish required aquarium with a minimum volume of 60 litres and a tank length of at least 60 cm. Water temperature should be maintained between 24°C and 28°C, with a pH range of 7.58.5 and a general hardness of 1025 dGH. A moderate water flow is preferred. To replicate their natural habitat, the tank should include sand (sifters) and shells (breeding/hiding).

Figure 8 Puffer (Brackish) can be kept singly or in a group, making them flexible additions to most setups. Keepers should be aware that this species may nip the fins of slow-moving or long-finned tankmates, is not safe with ornamental shrimp, will eat snails, and will defend a territory within the tank. The Figure 8 Puffer (Brackish) is typically available in one standard form.


Similar Species

Green Spotted Puffer (Brackish)

Dichotomyctere nigroviridis

Puffers
15 cm Highly Aggressive

The Green Spotted Puffer is a highly intelligent but notoriously aggressive fish. While frequently (and incorrectly) sold as a freshwater species, they strictly require brackish water that increases in salinity as they mature, eventually needing high-brackish or full marine conditions as adults. They have beak-like teeth that grow continuously and must be worn down by a diet of hard-shelled foods. Best kept entirely alone.

Dwarf Pea Puffer

Carinotetraodon travancoricus

Puffers
3 cm Aggressive

The Dwarf Pea Puffer is a tiny, fully freshwater pufferfish native to India. Despite their cute appearance, they are fierce micropredators and notorious fin-nippers. Modern husbandry standards strongly dictate they are highly social and must be kept in species-only shoals of 6 or more in heavily planted aquariums to disperse aggression and reduce stress. They require a steady diet of small snails and live/frozen foods.

Bumblebee Goby (Brackish)

Brachygobius xanthozonus

Gobies & Gudgeons
4.5 cm Mostly Peaceful

A miniature, bottom-dwelling goby famous for its striking black and yellow stripes. While they are often sold as freshwater fish and can survive in it temporarily, they are highly susceptible to fungal infections in fresh water and truly require a brackish setup (SG 1.002-1.005) to thrive long-term. They are notoriously picky eaters, often ignoring flakes in favor of live or frozen foods (like bloodworms or brine shrimp).

Mbu Puffer

Tetraodon mbu

Puffers
67 cm Aggressive

The largest freshwater pufferfish in the world, originating from the Congo River. Known for their 'puppy-like' intelligence and personality, they recognize owners and interact with them. However, they grow to massive sizes and possess a beak capable of crushing hard-shelled invertebrates. Unlike many puffers, they are true freshwater fish and do not need salt. They require massive filtration and a diet of hard foods (clams, snails) to keep their teeth trimmed.

Amazon Puffer

Colomesus asellus

Puffers
8 cm Mostly Peaceful

One of the few truly freshwater, community-safe pufferfish. Native to the Amazon basin, these energetic swimmers are known for their bumblebee-like stripes and erratic swimming patterns. Unlike most puffers, they are social and prefer to be kept in groups. CRITICAL WARNING: This species has the fastest-growing teeth of any puffer. They REQUIRE a daily diet of hard-shelled foods (snails, clams, crustaceans) or they will require manual dentistry (trimming) to prevent starvation.

Knight Goby

Stigmatogobius sadanundio

Gobies & Gudgeons
9 cm Semi-Aggressive

A distinct, high-bodied goby found in estuaries across South Asia. Unlike most bottom-dwelling gobies, the Knight Goby frequently hovers in the water column. While often sold as freshwater fish, they thrive best in slightly brackish water (SG 1.003-1.005) or very hard, alkaline freshwater. They are territorial and notorious fin-nippers, making them poor tankmates for Guppies or Bettas.