Can Arrowhead Puffer and Dojo Loach (Weather Loach) Live Together?

Arrowhead Puffer is a highly aggressive species (10/10), while Dojo Loach (Weather Loach) is peaceful (2/10). This notable difference means Arrowhead Puffer may occasionally assert dominance over Dojo Loach (Weather Loach).

Large aggression gap (8 points) between Arrowhead Puffer and Dojo Loach (Weather Loach) increases stress risk for the more peaceful fish.

Arrowhead Puffer and Dojo Loach (Weather Loach) 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: Hyperactive swimmers can stress shy, slow-moving species through constant motion.

Worth noting: Dojo Loach (Weather Loach) is a known jumper, so a tight-fitting lid is essential.

To improve the chances of a peaceful coexistence in this community tank: A larger aquarium with ample hiding spots can help diffuse aggression and give the less dominant fish space to retreat.

The safe temperature window for both species falls between 22°C and 24°C. Aim for the midpoint of this range (around 23.0°C) for optimal comfort.

Both fish can tolerate a pH between 6.5 and 7.5. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 5–15 dGH. Regular testing will ensure conditions stay within this range.

To house Arrowhead Puffer and Dojo Loach (Weather Loach) 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.

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: 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.