Upside-down catfish (Synodontis nigriventris) care guide

Group
Freshwater fish
Other names
Upside-down catfish, Blotched upside-down catfish, Upside-down syno
Family
Mochokidae (squeakers and upside-down catfishes)
Origin
Central Africa: the central Congo basin in the Democratic Republic of the Congo, Republic of the Congo and Cameroon.
Water
freshwater
Maximum size
9.6 cm
Temperature
22–28°C
pH
6–7.5
Hardness
3–18 dGH (estimated)
Minimum tank
80 litres
Care level
beginner
Temperament
peaceful

Care

This is the classic upside-down catfish: it spends much of its time swimming belly-up, especially under overhangs, leaves and the water surface. Its belly is darker than its back (the reverse of most fish), which suits this habit; the name nigriventris means dark belly. It is small, peaceful and one of the best Synodontis for smaller tanks. It is most active at dusk and night and likes to rest under cover by day, so give it overhanging rock, wood, tunnels or broad-leaved plants. The substrate type is not important. It does best in a small group, much like Corydoras. PlanetCatfish gives 22–28 °C and pH 6.0–7.5. No source we read gives a tank size, so the 80-litre minimum is an estimate for a small group. Like other Synodontis it has a hard head shield, serrated spines in the dorsal and pectoral fins, and makes audible squeaks by rubbing its pectoral spines when disturbed; take care when netting, as the spines catch in nets. Females are larger and plumper and become paler with age. It is similar to S. contracta, which has a larger head and much larger eyes. The IUCN lists it as Least Concern (assessed 2009). It is imported regularly. Sources: PlanetCatfish (planetcatfish.com/common/species.php?speciesid=334); Wikipedia (en.wikipedia.org/wiki/Synodontisnigriventris). Checked October 2026.

Diet

An undemanding omnivore that takes most prepared and live foods. Offer sinking pellets or tablets and flake, which it will also pick from the surface while upside down, plus frozen or live bloodworm, brine shrimp and Daphnia. In the wild it eats insects, crustaceans and plant matter.

Breeding

Rarely bred. One reported spawning happened by chance in a small container with clay pots and plastic pipes, after a varied, high-quality diet, soft slightly acidic water and noticeable temperature swings between about 25 and 28 °C. Offering several caves and pipes as spawning sites is worth trying. The young swim the normal way up at first and only start swimming upside down when about two months old.

Compatibility and tank mates

Peaceful with its own kind and other fish. A good choice for community tanks of small to medium-sized fish, including tetras, barbs, rasboras, peaceful West African cichlids and other peaceful catfish. Avoid fish small enough to fit in its mouth, such as tiny fry.

Last updated 5 October 2026. Community-edited care guide on Aquatic-Auctions.

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