红钩银板 · Redhook

Overview

Myloplus rubripinnis is recognized by a red anal fin edged in black. It is frequently sold alongside ordinary silver dollars but grows larger. Generous group housing, a plant-rich diet, and good water quality are central to its care.

Distribution & habitat

It occurs across much of northern South America, including the Amazon and Orinoco systems. Slow river sections with dense marginal or overhanging vegetation are typical settings.

Aquarium setup

An adult group needs a footprint around 180 × 38 cm or larger, with horizontal dimensions more important than extra height. Keep at least five and provide dim illumination with sheltered areas to reduce nervousness.

Living plants are actively consumed, and even durable species may need repeated replacement. Soft, suitable artificial vegetation can provide cover without relying on a carefully planted display remaining intact.

Diet & feeding

In nature it feeds chiefly on leaves from submerged or marginal vegetation, including terrestrial plants. Supply plenty of cucumber, zucchini, peas, and leafy greens, together with algae tablets, spirulina foods, or plant-based prepared diets. Small supplementary servings of worms or brine shrimp can add variety.

Behaviour & compatibility

It is generally peaceful with larger placid companions. Very small fish may be eaten, so herbivorous feeding tendencies do not remove the need to consider size. Larger peaceful bottom-dwelling catfishes are possible candidates.

Sexual dimorphism

The male may have a longer anal fin, but this remains an uncertain clue rather than a dependable sexing rule.

Notes

The red anal fin and black margin are more conspicuous than in familiar silver dollars, and adult space requirements are greater. Older literature often uses a former genus. Shared silver-dollar trade names do not establish that the fishes involved are the same species.