Can Colombian Shark Catfish (Brackish) and False Siamese Algae Eater (Stonelapping Minnow) Live Together?

Both Colombian Shark Catfish (Brackish) and False Siamese Algae Eater (Stonelapping Minnow) are moderately assertive species with an aggression score of 5/10. Their matching temperaments mean neither fish is likely to dominate the other in a shared aquarium.

Colombian Shark Catfish (Brackish) and False Siamese Algae Eater (Stonelapping Minnow) 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.

Worth noting: False Siamese Algae Eater (Stonelapping Minnow) is a known jumper, so a tight-fitting lid is essential.

The safe temperature window for both species falls between 22°C and 27°C. Aim for the midpoint of this range (around 24.5°C) for optimal comfort.

Both fish can tolerate a pH between 7.5 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 12–15 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.

To house Colombian Shark Catfish (Brackish) and False Siamese Algae Eater (Stonelapping Minnow) together, plan for an aquarium of at least 380 litres with a minimum length of 150 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), Established Algae (Otocinclus), Smooth Gravel (Sensitive Barbels), Driftwood (Digestion/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.

Colombian Shark Catfish (Brackish) and False Siamese Algae Eater (Stonelapping Minnow) 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.