Can Ceylon Puffer (Brackish) and Figure 8 Puffer (Brackish) Live Together?

Both Ceylon Puffer (Brackish) and Figure 8 Puffer (Brackish) are semi-aggressive species with an aggression score of 8/10. Their matching temperaments mean neither fish is likely to dominate the other in a shared aquarium.

Both Ceylon Puffer (Brackish) and Figure 8 Puffer (Brackish) are highly aggressive, increasing the risk of violent confrontations.

Ceylon Puffer (Brackish) and Figure 8 Puffer (Brackish) both frequent the Middle (Open Water) and Bottom (Substrate) region of the setup. This overlap can increase competition for space, so providing ample room and cover is important to keep both species comfortable.

Additional behavioural considerations to keep in mind: Two aggressive species housed together increases risk of fighting.

To improve the chances of a peaceful coexistence in this community tank: Provide a significantly larger tank (at least 50% more volume than the minimum) to allow both Ceylon Puffer (Brackish) and Figure 8 Puffer (Brackish) to establish separate territories. Add plenty of line-of-sight breaks using driftwood, rocks, and dense planting to reduce territorial confrontations. A larger aquarium with ample hiding spots can help diffuse aggression and give the less dominant fish space to retreat. Keep fin nippers in larger groups to distribute nipping behaviour among conspecifics rather than tank mates.

The safe temperature window for both species falls between 24°C and 28°C. Aim for the midpoint of this range (around 26.0°C) for optimal comfort.

Both fish can tolerate a pH between 7.5 and 8.5. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 12–25 dGH. Regular testing will ensure conditions stay within this range.

To house Ceylon Puffer (Brackish) and Figure 8 Puffer (Brackish) together, plan for an aquarium of at least 150 litres with a minimum length of 90 cm. This recommendation combines the stricter species minimums with a community-load allowance so the pairing has realistic long-term space and filtration headroom.

Because this pairing requires extra vigilance, include plenty of hiding spots — caves, driftwood, and dense plant clusters — so the less dominant fish can retreat when needed.

Specific environmental needs for this combination include: Shells (Breeding/Hiding), Sand (Sifters). Meeting these requirements will help both species thrive.

Both species do well with moderate (standard) water movement, so a standard filtration setup rated for the tank volume should suffice.