The Red Hook Silver Dollar (Myloplus rubripinnis) is a large, peaceful schooling fish recognized for its deep, round silver body and distinctive red-tipped anal fin that gives it its name. Native to the fast-flowing rivers and floodplains of South America, this species thrives in spacious aquariums with open swimming areas, driftwood, and hardy plants or artificial decor, as it may consume softer vegetation. They are best kept in groups of 5 or more, as schooling reduces stress and encourages natural behavior, and they pair well with other large, peaceful fish. Red Hook Silver Dollars are primarily herbivores, thriving on a diet of leafy greens, blanched vegetables, spirulina-based foods, and algae wafers, though they will also accept the occasional protein treat. Due to their adult size of up to 8–10 inches, they require a large aquarium with strong filtration, clean water, and stable conditions. With proper care, they can live over a decade and become centerpiece fish in community setups.
| Parameter | Requirement |
|---|---|
| Scientific Name | Myloplus rubripinnis (Red Hook Silver Dollar) |
| Tank Size | Minimum 100 gallons |
| Temperature | 24–28°C (75–82°F) |
| pH Range | 5.5–7.5 |
| Water Hardness | Soft to moderate (4–12 dGH) |
| Substrate | Sand or fine gravel with driftwood, open swimming areas |
| Diet | Herbivorous – vegetables, leafy greens, spirulina, algae wafers; occasional protein |
| Temperament | Peaceful, schooling, suitable for large community aquariums |
| Social Behavior | Best kept in groups of 5+ |
| Breeding | Rare in captivity; egg scatterer |
| Lifespan | 10–12+ years with proper care |