
Source: Wikimedia Commons
Myloplus rubripinnis
A large characin marked by a red, black-trimmed anal fin. It grows far beyond the Metynnis species sold as silver dollars, feeds heavily on plants, and needs a very large tank.
Myloplus rubripinnis is a large characin found widely through the Amazon and Orinoco basins. FishBase records 41.5cm TL and 2.5kg, gives pH 5.0-7.0, hardness to 15 dH and 23-27C, and describes it as gregarious and non-aggressive, preferring calm stretches of the main rivers where bankside vegetation overhangs the water. Seriously Fish gives 25.0cm SL, 23-27C, pH 6.0-7.0, 0-10 dGH and a base of at least 180 by 38cm. The red, black-trimmed anal fin is what separates it from the Metynnis species sold as silver dollars. In the wild it feeds chiefly on the leaves of submerged, marginal and even terrestrial plants, and it eats aquarium plants just as readily, so a planted display is hard to maintain alongside it. It is sometimes called a difficult fish, but given a large enough tank, the right food and good water it presents few problems.
Source: Wikipedia (CC BY-SA 4.0)
The Redhook Myleus lives 5-8 years.
The Redhook Myleus grows to About 25-41.5cm.
The ideal temperature for the Redhook Myleus is 23〜27℃.
Origin
South America (the Amazon and Orinoco basins)
Lifespan
5-8 years
Sources: Seriously Fish / FishBase
Edited & verified by: BreederDirect editorial team
The taxonomic, regulatory, and husbandry data on this page are compiled and verified against the authoritative primary sources below.
Sources: CITES Appendices (species not listed) / IUCN Red List
Regulations may change. Always verify the latest information with the relevant authorities.
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Size
About 25-41.5cm
Temperature
23〜27℃
Chiefly plant matter (courgette, cucumber, peas, greens, vegetable flake) with frozen bloodworm and brine shrimp
Seriously Fish suggests a base of at least 180 by 38cm, about 205 litres at 30cm depth, and stresses that length and width matter more than height. Juveniles can be grown on in something smaller, but plan the setup around the adult fish. Plants will be eaten, so even hardy species need replacing regularly.
Seriously Fish gives 23-27C, pH 6.0-7.0 and 0-10 dGH; FishBase gives pH 5.0-7.0, hardness to 15 dH and 23-27C. It is a big fish that eats heavily, so provide filtration and a water-change routine to match.
Keep at least five together. FishBase calls it gregarious and non-aggressive, but much smaller fish may be eaten. It works the middle and upper water, so large peaceful bottom-dwelling catfish such as plecos and doradids make good company.
In the wild it feeds chiefly on the leaves of submerged, marginal and terrestrial plants. Keep plant matter central in the aquarium too, with courgette, cucumber, peas and other greens plus spirulina and vegetable flakes. It takes most aquarium foods as well and is especially keen on bloodworm and brine shrimp.
Its size alone means any breeding attempt would call for substantial equipment.
FishBase lists it as IUCN Least Concern and not on the CITES appendices, but classifies it as traumatogenic, that is capable of causing injury, so mind the teeth when handling it. The main point to weigh is size: do not choose the tank for the juvenile you buy, and remember that a fish sold as a silver dollar will grow far larger if it is this species.
Advanced. This is an advanced-level species. It requires specialized equipment and advanced husbandry skills with precise environmental control.
The ideal temperature for Redhook Myleus is 23〜27℃. Avoid sudden temperature changes and maintain a stable environment.
The average lifespan of Redhook Myleus is 5-8 years. With proper care and nutrition, they can live a long and healthy life.
Redhook Myleus typically reaches About 25-41.5cm as an adult. Size may vary depending on care conditions and individual genetics.
Redhook Myleus feeds on: Chiefly plant matter (courgette, cucumber, peas, greens, vegetable flake) with frozen bloodworm and brine shrimp. Aim for a balanced diet with appropriate feeding frequency.
The price of Redhook Myleus varies significantly depending on morph, size, and lineage. Check our market price page for the latest pricing information.
Last updated: September 17, 2026