Can Figure 8 Puffer (Brackish) and Loricaria lundbergi Live Together?

Figure 8 Puffer (Brackish) is a semi-aggressive species (8/10), while Loricaria lundbergi is peaceful (1/10). This notable difference means Figure 8 Puffer (Brackish) may occasionally assert dominance over Loricaria lundbergi.

Large aggression gap (7 points) between Figure 8 Puffer (Brackish) and Loricaria lundbergi increases stress risk for the more peaceful fish.

Figure 8 Puffer (Brackish) and Loricaria lundbergi both frequent the 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: Aggressive fish may bully and stress shy, slow-moving species. Hyperactive swimmers can stress shy, slow-moving species through constant motion.

Worth noting: Loricaria lundbergi is nocturnal and will be most active after lights-out, naturally reducing daytime encounters.

The safe temperature window for both species falls between 25°C and 28°C. Aim for the midpoint of this range (around 26.5°C) for optimal comfort.

The pH requirements of Figure 8 Puffer (Brackish) (7.5–8.5) and Loricaria lundbergi (5–7) do not overlap, making it impossible to satisfy both species simultaneously.

For general hardness, the shared comfort zone is 10–10 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.

To house Figure 8 Puffer (Brackish) and Loricaria lundbergi together, plan for an aquarium of at least 110 litres with a minimum length of 80 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: Sand (Sifters), Shells (Breeding/Hiding), Driftwood (Digestion/Hiding), Leaf Litter/Blackwater. 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.

Figure 8 Puffer (Brackish) and Loricaria lundbergi are the kind of pair that can look acceptable in a shop but become a maintenance problem at home. The main risk is not a single number in the chart; it is the way incompatible behavior, water needs, or pressure on space compounds over time once both fish are established in the same tank.