Upside-down Catfish
Synodontis nigriventris
Also sold as Blotched upside-down catfish
Upside-down Catfish (Synodontis nigriventris) is a peaceful freshwater fish that reaches about 10 cm (3.9 in) and swims along the bottom. It wants 75–82°F (24–28°C) and pH 6–7.5, is kept in groups of 3 or more, and needs a tank of at least 70 L (18 gal).
At a glance
| Type | Fish |
|---|---|
| Adult size | 10 cm (3.9 in) |
| Minimum tank | 70 L (18 gal) |
| Group size | 3 or more |
| Temperature | 75–82°F (24–28°C) |
| pH | 6–7.5 |
| Temperament | Peaceful |
| Eats shrimp | Yes |
Before it goes in
- Upside-down Catfish needs at least 70 L (18 gal). The smallest size in this library that clears that is the 20 Gallon High.
- Keep 3 or more. Below that it hides, colours down and is far more likely to be picked on.
- It eats small fish and shrimp — anything under about 3.5 cm (1.4 in). In this library that means Cherry Shrimp, Crystal Red Shrimp and Bamboo Shrimp.
- It holds at 75–82°F (24–28°C). That shares a window with Betta and Cherry Shrimp, but not with Goldfish and Dojo Loach.
- A group of 3 takes up roughly 72% of what a 20 Gallon High will comfortably hold, so plan the rest of the stock around it.
What tank size does it need?
At least 70 L (18 gal). The smallest size here that clears it is the 20 Gallon High.
How many should I keep?
3 or more. Fewer than that and it spends its time hiding instead of out in the open.
Will it eat shrimp?
Yes. Shrimp are food to it, so pick one or the other.
What water does it want?
75–82°F (24–28°C), pH 6–7.5.
Good tank mates
- Tank mates from this library that share its temperature window, are peaceful and eat neither it nor its young: Bristlenose Pleco, Celestial Pearl Danio, Molly, Otocinclus and Ramshorn Snail.
- Plants that hold up with it: Hygrophila corymbosa 'Siamensis', Water Sprite, Anubias nana 'Petite' and Cryptocoryne wendtii.
Often compared with
| Upside-down Catfish | Pictus Catfish | Glass Catfish | |
|---|---|---|---|
| Adult size | 10 cm | 12 cm | 6.5 cm |
| Min tank | 70 L | 243 L | 81 L |
| Group | 3+ | 6+ | 6+ |
| Temperature | 75–82°F (24–28°C) | 72–77°F (22–25°C) | 68–79°F (20–26°C) |
| Eats shrimp | Yes | Yes | Shrimplets only |
More livestock
Sources (3) · checked Sep 2026
- What it eatsaquaticarts.com
- What it eatsfishkeeper.co.uk
- Mature tankseriouslyfish.com