Species profile
Silver Dollar
Metynnis hypsauchen
Peaceful
Moderate care
650 L minimum aquarium
18–20 cm adult size
Midwater
Minimum group: 6
About this species
General notes for hobby use.
Large, skittish shoaling characin; adult groups need a long, broad aquarium and are poor choices for planted displays.
Water parameters
Suggested general range for long-term care.
Temperature
24–28 °C
pH
6–7.5
GH
Up to 18 dGH
KH
Not yet documented
Flow preference
Moderate–high
Data confidence
Verified
Behaviour
General behaviour traits used by TanksConnected compatibility checks.
Minimum group size
Minimum group: 6
Tank zone
Midwater
Territory level
None
Predation risk
Tiny fry
Bioload factor
2.8
Maintain a proper shoal to reduce nervous behaviour. Sudden movement can trigger fast panic dashes, so leave open swimming room and use a secure cover.
Compatibility flags
Quick cautions for common tank-planning issues.
Fin nipper
No
Plant safe
Caution
Shrimp safe
No / caution
Snail safe
Yes
Cave breeder
No
Digs substrate
No
Jump risk
Yes
Natural history & care
Research-backed context for long-term aquarium care.
Lifespan
Not yet documented
Diet type
Herbivore
Minimum aquarium volume
650 L
Minimum footprint
180 × 60 cm
Accepted scientific name
Metynnis hypsauchen
Alternative names
Silver Dollar, Plain Metynnis
Native range
Tropical South America in the Amazon and Guiana-region drainage systems.
Natural habitat
Occurs in rivers and floodplain waters; aquarium layouts should combine open swimming space with cover while avoiding sharp décor.
Diet & feeding
Strongly plant-oriented omnivore/herbivore. Supply substantial vegetable matter; soft aquarium plants are likely to be eaten.
Breeding & sexing
Research-backed guidance for identifying sexes and reproductive behaviour.
Sexing
Mature males can show a more extended or differently coloured anal fin; females are generally fuller when gravid.
Breeding
Egg-scattering characin; eggs fall among plants or spawning media and hatch after roughly several days depending on conditions.