Silver Dollar Fish (Metynnis argenteus)

Silver dollar fish

Last updated on September 19th, 2022 at 06:07 pm

Silver dollar fish (Metynnis argenteus) is an excellent fish for beginners and experts alike, especially in the aquarium hobby. The silver dollar fish is peaceful, hardy, and easy to care for, making it one of the most popular species of tropical freshwater fish on the market today.

By now, most aquarium hobbyists have heard of the silver dollar fish, which also goes by the name Metynnis argenteus. This fish is known for its distinctive appearance and its vibrant colors, making it quite a popular choice among aquarium hobbyists who are interested in adding some additional color to their tanks.

When you’re ready to add silver dollar fish to your aquarium, it’s important to make sure that your tank meets the needs of this unique species. If you’re interested in learning more about how to care for silver dollar fish or how to choose an appropriate tank for them, then you are on the right page here!

Silver dollar fish are an excellent fish for beginners and experts alike, especially in the aquarium hobby. They are peaceful, hardy, and easy to care for, making them one of the most popular species of tropical freshwater fish on the market today.

Metynnis argenteus has become one of the most popular feeder fish among pet owners and aquarists due to its striking appearance and ease of care in captivity. But what exactly are silver dollar fish? And how can you keep them healthy and thriving in your home aquarium?

What is the silver dollar fish?

The silver dollar fish is a small species of tropical freshwater fish from South America. Their average lifespan is about three years, but some individuals have been known to live for as long as ten years. The scientific name for silver dollar fish comes from their distinctive metallic silver coloration. There are four subspecies of silver dollar fish that vary in size and coloration.

Parachromis managuensis (Jaguar Cichlid)

They are native to Northern Argentina, Southern Brazil, Uruguay, and Paraguay. Their habitat consists of slow-moving water bodies with sandy bottoms — like ponds, lakes, and ditches — and they enjoy temperatures between 68°F (20°C) and 82°F (28°C). They tend to hide among aquatic vegetation during daylight hours.

Origin and descriptions

Silver dollar fish

The silver dollar fish, Metynnis argenteus, is a freshwater tropical fish that lives in South America. It is often found near large rivers. The Metynnis argenteus belongs to a small group of fishes referred to as Serrasalminae. This group also includes several other species of silver dollars, including both fresh and brackish water types. These are all separated into different genera.

The silver dollar fish is actually included in its own genus, called Metynnis. The name for that comes from two words; one part of it originates from mytinis, which means fish or swim in Greek. The last part translates to argentum, which is Latin for silver or silvery. That refers to their appearance and coloration.

Where does the name silver dollar come from?

You may have heard someone refer to Metynnis argenteus as a silver dollar fish, but you might be wondering why it’s called that. In reality, they aren’t actually silver dollars. Although they used to be commonly known as silver dollars, today they are named after their resemblance to old coins of that value. The name comes from their size and shape; with adults reaching up to seven inches in length and having a silvery appearance.

The common name silver dollar is derived from the Spanish Milled Dollar coins minted between 1732 and 1873 which were roughly round, made of 8 release or 96 U.S. cents worth of precious metal, weighed approximately one ounce, and had a diameter slightly larger than 11⁄4 inch (31mm). A similar coin still in circulation is $1 USD coin whose design was updated in 2009. The silver dollar only applies to species whose natural habitat is freshwater.

Species profile

Silver dollar fish

The silver dollar fish is part of a group of freshwater fish in South America. It has been introduced to other areas, such as Africa and Australia. In some areas, it has become an invasive species that threatens local ecology and biodiversity. They can grow up to six inches long, but often only reaches half that size in captivity. It typically lives around ten years.

Glofish Tetra Care Guide

As juveniles, they are aggressive and may nip at the tails or fins of other small fish. As adults, however, they lose their aggressiveness and become more passive swimmers. Like all Metynnis argenteus species, male juveniles develop bright coloration during mating season — they turn bright red on their dorsal fins with black lines near their mouths and gills. Females remain mostly silver throughout life.

Metynnis argenteus gets its name from its resemblance to the American silver dollar coin and its size, which can grow to 6 inches in length (15.2 cm). They are commonly found in South America and Brazil, particularly in the Amazon River basin. Despite their resemblance to a common fish in the United States, they aren’t kept as pets too often because of their large size and potential aggression towards other fish and humans.


Metynnis argenteus can be found in tropical areas such as South America, Africa, India, and Asia. They enjoy living in rivers and lakes but are sometimes found in man-made bodies of water such as ponds and lagoons. These fish tend to hang out near shorelines where there are plenty of rocks for them to hide behind during the breeding season. In times when food sources aren’t plentiful, these fish also tend to head toward shallow waters for easier access to food sources.

Silver dollar fish size

The silver dollar fish can grow to an average size of 15 cm (6 inches) in length.

Silver dollar fish tank size

The minimum recommended tank size is 75 gallons or more (in case you want to add more than 1 fish)

Tank set up

These fish can grow to about 6 inches in length and need ample space to swim and play. A larger tank will also have more oxygen, which means cleaner water conditions for your fish. Remember that it’s not just the size that matters when considering a new home for your fish, but location as well. Choose an area of your home that has consistent temperatures between 65-77 degrees Fahrenheit and where you can keep humidity levels between 55-65%.

If you live in a dry climate, adding a small aquarium filter may be necessary to maintain these percentages. You don’t want them too high or else mold could appear on your aquarium walls and floors. Additionally, make sure to provide shade and cover with plants, artificial plants, or rocks – they’ll enjoy somewhere they can hide from time to time!

Heros Efasciatus (Red Spotted Severum)

Silver dollar fish tank mates

While silver dollar fish may be small, they’re also very territorial. This means they can (and will) nip at other fish in their tank. Make sure you keep these fish away from any species that are fin-nippers—such as bettas and angelfish—and don’t put them with larger species, like koi or cichlids. Smaller bottom feeders, like tetras and rasboras, are ideal tank mates for silver dollar fish.

Silver dollar fish breeding

Silver dollar fish

Silver dollar fish are relatively easy to care for and aren’t difficult to breed. Breeding silver dollar fish is possible because they have several distinct phases within their life cycle – both sexually immature and mature males; sexually immature females; mature females carrying fertilized eggs; and eggs themselves.

Metynnis argenteus are egg scatterers, which means eggs will be laid outside of a nest and left to develop and hatch on their own. Eggs can take up to 30 days to hatch depending on water temperature and water conditions. Metynnis argenteus juveniles have been observed up to 2.8 inches in length after three months of development.

Are Silver dollar fish aggressive or peaceful?

The peaceful nature of silver dollar fish makes them perfect as community tank fish. They get along very well with other tropical fish, both large and small. If you are keeping them in an aquarium with invertebrates, however, keep in mind that some species do have issues sharing space with snails or shrimp.

Silver dollar fish care

Silver dollar fish

The silver dollar fish is hardy and durable. The majority of its time should be spent swimming in cooler water with temperatures between 74 and 80 degrees Fahrenheit. Because of their durability, it is crucial that you provide your fish with high-quality foods, as well as lots of hiding places. This can be accomplished by putting plants into your tank to create living spaces for your fish. If there are not enough plants to hide in, use silk plants or rocks to simulate cover.

Silver dollar fish diet

In their natural habitat, Metynnis argenteus feeds on various types of insects and small fish. If you have an aquarium, you can expect that your silver dollar fish will also eat just about anything: brine shrimp, daphnia, mosquito larvae, bits of plants, and algae. To ensure that your pet gets all the nutrition it needs in its diet, add high-quality flake food to supplement live foods.

Brichardi Fish Care - Fairy Cichlid

A steady supply of live food adds variety as well as essential nutrients, like calcium. When you’re adding more than one fish, make sure they’re from different species — silver dollars don’t tend to get along with other species too well.

Water parameters

Silver dollar fish

The ideal water should have a temperature of 22-25C, pH of 7.2–7.8, hardness around 10–15 dGH, and carbonate hardness around 4–6°dKH; but temperatures of 18-20 degrees C are optimal for breeding. Males are larger than females and generally range in size from 4 to 6 inches. Fins are long and pointed in appearance.

Silver dollar fish lifespan

Their average lifespan is slightly less than 10 years, although, with good care and the right conditions, they can live for more than 10 years in captivity.

Parasites and diseases

The silver dollar fish are susceptible to parasites and diseases like most other fish. It is important to provide them with optimum living conditions, otherwise, they will fall ill. A healthy silver dollar fish should be alert and its fins should be firm and well-shaped. Also, it should move in an agile manner (wiggle its butt).

If you notice that your fish are not as lively as they used to be, they might have been infected by parasites or diseases. In that case, treatment is required. Read more about treatment for parasites and diseases here.


Humans are one of only two predators to threaten silver dollar fish. The other predator is a much larger fish, such as barracuda or grouper, which will eat smaller silver dollar fish whole. Some other species have also been known to take on these baby silver dollars for food as well. These include tarpon and snook.

Do Silver dollar fish make good pets?

The silver dollar (Metynnis argenteus) fish is an amazing, bright, and active fish that can become a great pet. They are also known as Argenteus, silver dollar cichlid, Argente spotted cichlid, and fernandyi. They belong to Metynnis genus of fishes.