Can Yellow Bullhead Catfish and Zebra Oto Live Together?

Yellow Bullhead Catfish is a moderately assertive species (6/10), while Zebra Oto is peaceful (0/10). This notable difference means Yellow Bullhead Catfish may occasionally assert dominance over Zebra Oto.

Large aggression gap (6 points) between Yellow Bullhead Catfish and Zebra Oto increases stress risk for the more peaceful fish.

Yellow Bullhead Catfish and Zebra Oto 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.

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: Aggressive eaters may outcompete shy fish for food, leading to malnutrition. Shrimp eaters may also prey on very small nano fish.

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

The safe temperature window for both species falls between 21°C and 26°C. Aim for the midpoint of this range (around 23.5°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 4–10 dGH. Regular testing will ensure conditions stay within this range.

To house Yellow Bullhead Catfish and Zebra Oto together, plan for an aquarium of at least 500 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), Driftwood (Digestion/Hiding), Smooth Gravel (Sensitive Barbels), Established Algae (Otocinclus), Plants - Densely covered. Meeting these requirements will help both species thrive.

Note a potential conflict in setup requirements: Yellow Bullhead Catfish is a plant destroyer, which conflicts with Zebra Oto's requirement for live plants. Compromise where possible or prioritise the more critical need.

Both species do well with moderate (standard) water movement, so a standard filtration setup rated for the tank volume should suffice.

Yellow Bullhead Catfish and Zebra Oto 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.

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

Because Yellow Bullhead Catfish is a fast, competitive feeder, consider using sinking pellets or feeding at opposite ends of the setup to ensure Zebra Oto receives an adequate share.