Upside-Down Catfish: Tank Size, Tank Mates & How Many

What size tank do upside-down catfish need?

At least 30 gallons (114 liters) for a group of 3. The smallest standard tank that works is the 29 gallon. A bigger tank is always easier to keep stable. We give the size for an adult fish in a proper group, because the small fish in the shop will grow. Scientific name: Synodontis nigriventris.

How many upside-down catfish in each tank size?

This is how many each standard tank carries comfortably if upside-down catfish are the only fish in it. Share the tank with other species and the number goes down.

Tank	How many upside-down catfish
5 gallon	Too small
10 gallon	Too small
20 gallon long	Too small
29 gallon	up to 6
40 gallon breeder	up to 8
55 gallon	up to 11
75 gallon	up to 16
125 gallon	up to 26

Check upside-down catfish against your own tank and other fish

Good to know

Keep at least 3. In smaller numbers they are stressed, or one gets picked on.

Tank mates for upside-down catfish

These animals like the same water, are a safe size, and have a temper that fits. It is a match on paper: always watch new tankmates for the first week.

Poor matches

Fancy goldfish: Goldfish do best with other fancy goldfish.
Oscar: Oscar is aggressive and will bully or kill peaceful fish such as upside-down catfish.
Molly: They need different water: Upside-down catfish likes a pH of 6–7.5, molly likes 7.5–8.5.

Questions and answers

What size tank do upside-down catfish need?

At least 30 gallons (114 liters) for a group of 3. The smallest standard tank that works is the 29 gallon. A bigger tank is always easier to keep stable.

How many upside-down catfish should be kept together?

At least 3. Upside-down catfish are social animals and only behave naturally in a group. More is better if the tank has room.

Can upside-down catfish live in a 10 gallon tank?

No. Upside-down catfish needs at least 30 gallons (114 liters).

What temperature do upside-down catfish need?

72–81 °F (22–27 °C), with a pH of 6–7.5. In most homes that means a heater.

Can upside-down catfish live with a betta?

Usually, yes, in a tank of 30 gallons (114 liters) or more. They like the same water: 75–81 °F (24–27 °C). Every betta has its own temper, so watch closely for the first week and have a spare tank ready.

More fish

Adult size, tank size and water ranges follow the mainstream care consensus (Seriously Fish species profiles and FishBase maximum lengths). Where sources differ we use the more cautious figure. Stocking numbers come from our stocking calculator.