Can Striped Raphael Catfish and Threadfin Rainbowfish Live Together?

Striped Raphael Catfish is a peaceful species (2/10), while Threadfin Rainbowfish is peaceful (1/10). This modest difference means Striped Raphael Catfish may occasionally assert dominance over Threadfin Rainbowfish.

In terms of spatial distribution, Striped Raphael Catfish prefers the Bottom (Substrate) zone, whereas Threadfin Rainbowfish occupies the Top (Surface) and Middle (Open Water) zones. Because they use different levels of the water column, territorial disputes are less likely and the tank will appear more balanced.

There is a critical concern: the Piscivore (Eats small/nano fish) behaviour of one fish directly conflicts with the Nano / Bite-sized (Predation Risk) trait of the other — piscivorous fish will prey on nano-sized tank mates..

Additional behavioural considerations to keep in mind: Hyperactive swimmers can stress shy, slow-moving species through constant motion. Aggressive eaters may outcompete shy fish for food, leading to malnutrition. Shrimp eaters may also prey on very small nano fish.

Worth noting: Striped Raphael Catfish is nocturnal and will be most active after lights-out, naturally reducing daytime encounters. Also, Threadfin Rainbowfish is a known jumper, so a tight-fitting lid is essential.

The safe temperature window for both species falls between 24°C and 29°C. Aim for the midpoint of this range (around 26.5°C) for optimal comfort.

Both fish can tolerate a pH between 6 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 2–12 dGH. Regular testing will ensure conditions stay within this range. An aquarium test kit is recommended for monitoring.

To house Striped Raphael Catfish and Threadfin Rainbowfish together, plan for an aquarium of at least 240 litres with a minimum length of 120 cm. This accounts for the larger species' space requirements with an additional 20 % buffer to reduce territorial tension.

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), Driftwood (Digestion/Hiding), Plants - Densely covered, Plants - Floating. 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.

Feeding time deserves special attention with this pairing. Striped Raphael Catfish is a known shrimp eater and may prey on small invertebrates or nano fish like Threadfin Rainbowfish. Threadfin Rainbowfish is an aggressive eater that may prevent Striped Raphael Catfish from getting enough food.

Because Threadfin Rainbowfish is a fast, competitive feeder, consider using sinking pellets or feeding at opposite ends of the setup to ensure Striped Raphael Catfish receives an adequate share.