Synodontis contractus
Big-nosed Upside-down Catfish
Formerly Synodontis contracta
Last revised 2026Edit this page
On this page11 sections
Quick factsEdit
Difficulty5 of 8 measures
- Space
- medium tank
- Water
- needs a steady pH
- Temp
- flexible
- Diet
- unknown
- Temperament
- unknown
- Social
- needs to be in a group
- Compatibility
- unknown
Other demands
Each of these can raise the rating on its own, whatever the measures above say.
- Hardiness
- hardy
The big-nosed upside-down catfish, Synodontis contractus, is a small Synodontis from the Democratic Republic of Congo and Republic of Congo. Often confused with S. nigriventris, it is easily told apart by its larger eyes and broad mouth and head, and it spends most of its time swimming inverted. It should be kept in groups of at least three or four, and can be delicate and prone to disease when first imported.
Distribution
EditFound only in the Democratic Republic of Congo and the Republic of Congo. It occurs in small ponds, backwaters and creeks, often in large numbers.
Habitat
Write a noteEditFound only in the Democratic Republic of Congo and the Republic of Congo. It occurs in small ponds, backwaters and creeks, often in large numbers.
Aquarium size
Write a noteEdit60 ∗ 30 ∗ 30 cm24 ∗ 12 ∗ 12 in
Maintenance
Write a noteEditA dimly lit aquarium with a soft substrate and rocks, pieces of driftwood and twisted roots arranged to form hiding places suits this species. Broad-leaved plants, such as Anubias or Echinodorus and floating vegetation are also recommended, as the fish like to roost under these.
Water conditions
EditTemperature: 22 – 27 °C72 – 81 °F
pH: 6.2-7.2
Hardness: 3-15 dH
These recommendations come from this profile’s own figures. They contain affiliate links, so we may earn a commission.
Diet
Write a noteEditSynodontis are omnivorous and are most unfussy in terms of feeding. Frozen, live and dried foods are all accepted. It also relishes vegetable matter in the form of shelled peas, cucumber etc., which it will rasp at with the teeth in its lower jaw. Unlike most others in the genus, S. contractus will often feed from the surface in its typical inverted style.
Behaviour and compatibility
Write a noteEditOne of the most gentle members of the genus, S. contractus can be combined with most peaceful species successfully. The most appropriate tankmates include African tetras, dwarf cichlids such as Pelvicachromis or Anomalochromis and small mormyrids. This species should be maintained in groups of at least 3-4 individuals, as this will give them confidence and encourage them to be seen more often.
Sexual dimorphism
Write a noteEditCannot be sexed by the genital papilla technique as it is too small, although the same dimorphism is apparent. It is therefore difficult to sex, although adult females are generally plumper than males.
Reproduction
Write a noteEditHas been spawned in aquaria but the eggs did not hatch.
Notes
EditOften confused with the similar S. nigriventris, this species is imported infrequently. It is easily distinguished from nigriventris by its larger eyes and broad mouth and head. These features give rise to the common name "Big-nosed upside-down catfish". S. contractus spends the majority of its time swimming in an inverted position and this, along with its exaggerated facial features, make it a characterful and interesting addition to the community aquarium. It is also known as the Bug-eyed Squeaker.
One point that should be noted, is that this species can be quite delicate and susceptible to disease when it is first imported. Extra care with regards to water quality should be taken during the acclimatisation period. Once settled, it usually proves quite hardy.
Species images · 1
These photographs are used with each photographer's permission.
Send a photographHow the name has changed
Renamed from Synodontis contracta to Synodontis contractus.
2026Eschmeyer's Catalog of Fishes: genera, species, references
Distribution
Profile completeness20 of 24
83% complete
Also missing: etymology.
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