Can Arfak Rainbowfish and Figure 8 Puffer (Brackish) Live Together?
Arfak Rainbowfish and Figure 8 Puffer (Brackish) are not recommended as tank mates due to incompatible water types. Housing these species together is likely to result in stress, health problems, or direct harm to one or both fish.
At a Glance
Can your tank handle Arfak Rainbowfish and Figure 8 Puffer (Brackish)?
Compatibility is only part of the answer. Test both fish with your real tank size, current stock, and maintenance needs to see if you have enough space and a safe stocking level before you add them.
Shared setup supplies
We may earn from qualifying purchases
Behaviour & Temperament
Arfak Rainbowfish is a peaceful species (2/10), while Figure 8 Puffer (Brackish) is semi-aggressive (8/10). This notable difference means Figure 8 Puffer (Brackish) may occasionally assert dominance over Arfak Rainbowfish.
Large aggression gap (6 points) between Arfak Rainbowfish and Figure 8 Puffer (Brackish) increases stress risk for the more peaceful fish.
Arfak Rainbowfish and Figure 8 Puffer (Brackish) both frequent the Middle (Open Water) region of the setup. This overlap can increase competition for space, so providing ample room and cover is important to keep both species comfortable.
Worth noting: Arfak Rainbowfish is a known jumper, so a tight-fitting lid is essential.
Water Parameters
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. Maintaining a stable value within this band is more important than hitting an exact number.
For general hardness, the shared comfort zone is 10–15 dGH. Regular testing will ensure conditions stay within this range.
Crucially, these species require different water types — one needs freshwater while the other requires brackish conditions. This is a hard barrier to keeping them together.
Water care products
We may earn from qualifying purchases
Tank Setup
To house Arfak Rainbowfish and Figure 8 Puffer (Brackish) together, plan for an aquarium of at least 200 litres with a minimum length of 120 cm. This recommendation combines the stricter species minimums with a community-load allowance so the pairing has realistic long-term space and filtration headroom.
Providing a mix of open swimming space and sheltered areas with rocks, driftwood, or plants will keep both species comfortable and allow natural behaviour.
Specific environmental needs for this combination include: Plants - lighly covered, Smooth Gravel (Sensitive Barbels), Sand (Sifters), Shells (Breeding/Hiding). Meeting these requirements will help both species thrive.
Both species do well with high (river/stream) water movement, so a standard filtration setup rated for the tank volume should suffice.
Suitable Tank Sizes
Standard aquarium sizes large enough for both Arfak Rainbowfish and Figure 8 Puffer (Brackish).
55 Gallon Standard
60 Gallon Breeder
75 Gallon Standard
90 Gallon Standard
125 Gallon Standard
150 Gallon High
Feeding products to consider
We may earn from qualifying purchases
.webp?2026-04-25T14%3A35%3A38.022Z)
Frequently Asked Questions
Can Arfak Rainbowfish and Figure 8 Puffer (Brackish) live together?
No. This combination is not recommended. Key incompatibilities — such as different water type needs — make cohabitation unsafe.
What size tank do Arfak Rainbowfish and Figure 8 Puffer (Brackish) need?
A minimum of 200 litres (tank length at least 120 cm) is recommended. This provides enough space for both species to establish their own areas and reduces the likelihood of territorial disputes.
What water temperature is best for Arfak Rainbowfish and Figure 8 Puffer (Brackish) together?
Keep the aquarium between 24°C and 28°C. A target of around 26.0°C sits comfortably within both species' preferred ranges.
Are Arfak Rainbowfish or Figure 8 Puffer (Brackish) aggressive?
Arfak Rainbowfish is peaceful (2/10) and Figure 8 Puffer (Brackish) is semi-aggressive (8/10). The gap in aggression levels means the calmer fish may experience stress from the more assertive one.
What pH do Arfak Rainbowfish and Figure 8 Puffer (Brackish) need?
Both species overlap in the 7.5–8 pH range. Consistency is key — avoid sudden swings, and test regularly to stay within this window.
Will Figure 8 Puffer (Brackish) nip Arfak Rainbowfish's fins?
Figure 8 Puffer (Brackish) is a known fin nipper. If Arfak Rainbowfish has long or flowing fins, there is a real risk of fin damage. Keeping Figure 8 Puffer (Brackish) in a larger group can help redirect nipping behaviour toward conspecifics.
How do I manage Figure 8 Puffer (Brackish)'s territorial behaviour?
Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Figure 8 Puffer (Brackish) space to claim a territory without encroaching on the other fish's area. Adding décor that divides the tank into distinct zones works especially well.
Related Comparisons
Arfak Rainbowfish & Banded Rainbowfish
·
Arfak Rainbowfish & Axelrod's Rainbowfish
·
Arfak Rainbowfish & Boeseman's Rainbowfish
·
Arfak Rainbowfish & Dwarf Neon Rainbowfish (Praecox)
·
Arfak Rainbowfish & Forktail Blue-eye
·
Arfak Rainbowfish & Gertrude's Spotted Blue-eye
·
Figure 8 Puffer (Brackish) & Green Spotted Puffer (Brackish)
·
Figure 8 Puffer (Brackish) & Fahaka Puffer
·
Figure 8 Puffer (Brackish) & Mbu Puffer
·
Figure 8 Puffer (Brackish) & Arrowhead Puffer
·
Figure 8 Puffer (Brackish) & Dwarf Pea Puffer
·
Figure 8 Puffer (Brackish) & Amazon Puffer
·