The Silver Dollar fish is a sizzling beauty from the American continent and thus is named after its resemblance to the dollar coin of the USA.

The bright silvery scales and a spherical body mesmerize with a reflective, mirror-like appearance.

It has marked itself as a renowned, unusual, eye-catching species that has long become a popular addition to the aquarium. Their tranquil and pleasant nature makes them community tank compatible.

There are many species of these fishes you can choose from, and it requires very little time and effort to maintain their health and wellbeing.

We will go over how to care for Silver Dollar fish, as well as finer details about its appearance, compatibility, and much more..

Fact: There are numerous species of Silver Dollar fish in the world. These species are genetically complementary to the Pacu fish found in South America.

Species Specifics

Scientific Name Metynnis argenteus
Family Characidae
Common Names Dollar Coin fish, Silver Dollar
Water Type Freshwater
Color Silver
Maximum Size 14 cm
Origin Brazil
Maximum Lifespan 10 – 12 years

Native Habitat

Initially discovered in the early twentieth century (1923) by a scientist, this fish has been popular in the fishkeeping world.

According to scientific research, this fish is inherently found in the freshwater aquascapes of South America, particularly in the Tapajos River of Brazil.

The Silver Dollar Fish is also seen in Venezuela and Guyana’s river inlets and tributaries. They have been located traversing the freshwaters areas, searching for food and spawning grounds.

These rivers’ passive and serene depths are the natural dwelling grounds of these active and lively fish. But their specific area of origin has not yet been pinpointed on the map.

Maximal Dimensions of the Fish

The babies of these fish are ball-shaped, but with maturity and enough tank space, these fish can grow more.   

The maximum size of Silver Dollar fish is about 5.5 inches, but there are few exceptions when they are recorded to obtain an expanded length of around 9 inches in the wild.

Aesthetics, Shape, and Color

The fish’s body is slightly discoid with a flattened structure, and tapering projections extend from the cardinal directions of the circumference.

It has lustrous but small scales while the caudal and anal fins are transparent, similar to the fletching of a traditional arrow. The pectoral fins are thin as a leaf and are somewhat lucid in appearance to the human eye. Meanwhile, the anal fins that look like a hook are sometimes covered with a brush mark of red or orange and stick out oddly from the fish’s body.

The Silver Dollar fish looks gorgeous in its silvery glittering appearance. It normally has a light green or bluish hue and dark black or brown mini-spots over the body. The only bright color they have is red, which is present on the corners of the anal fins.

Varieties of Silver Dollar Fish

Silver dollar fish is categorized into multiple categories depending upon their size, and looks. The names of these sub-species specifically describe the peculiar characteristics they possess. Some of them are listed below.

  • Red Hook Silver Dollar
Red Hook Silver Dollar

It is dimensionally a photocopy of the original fish, but the only distinction is the horizontal patch of reddish color over the anal fin. These are considered one of the largest Silver Dollar fish as they can attain a length of 16 inches.

  • Blue Hook Silver Dollar
Blue Hook Silver Dollar

The fish appears light blue with a black strip slanting from the dorsal to the anal fin and hence is also referred to as the Black-Barred Silver Dollar. These are mostly found in the Amazon River basin around Brazil and can also reach up to 16.5 inches in size becoming the largest Silver Dollar fish..

  • Striped Silver Dollar
Striped Silver Dollar

These are also known as Banded Silver Dollar fish. It resembles a tiger or zebra with a gray color in the background and dark stripes printed on the belly. The strips are specific to the variety of this species. The anal fins are quite noticeably larger than other varieties.

  • Spotted Silver Dollar
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Spotted Silver Dollar

They are a common variety and have similar quadrilateral dimensions with rounded edges like the original species. The distinction is that they have dark spots with red pectoral fins on their bodies.

The Differences in Males and Females

The Silver Dollar fish have quite a few distinctions in their physical features that can be used to identify their gender. The significant differences are listed below.

  • The male fish have a pointy and elongated anal fin, whereas females have a shorter anal fin. If both the genders are in the same tank, we can spot the difference quickly.
  • The male fish have an orange or red shade over anal fins, absent in the females.
  • The male fishes have a band of dark color on the outline of the tail fin, while females do not bear such a mark.
  • During mating season, females carry eggs and can have a rounder and puffier belly than males.  This difference in physicality can be seen only during a specific period.
  • Dark spots appear under the gills of the males during the breeding season, which cannot be seen in the females.

How Old do Silver Dollar Fish Live?

A high standard dietary habit and favorable water conditions inside the tank can suggest a better life expectancy, but is highly unusual.

The life span of a Silver Dollar fish depends on multiple factors from its living environment, to feeds. It can easily complete ten years in a captive region provided that it possesses optimal care and nutrition from its owners.

Cost And Obtainability

It is not an endangered species, as to satiate the demands of customers, the fish is bred in an adequate quantity, making it a low-cost aquatic.

When they are babies, the average price of a Silver Dollar fish is estimated to be around $5, but it may go slightly above the range depending upon the fish’s age, size, and delivery location.

These fish have regularly been in demand by keepers and enthusiasts from all over the world. One can purchase them directly from the fish stores or via the internet.

Care Guideline

Quick Tips
Degree of Care Easy
Breeding Egg layer
Social Behavior Friendly
Diet Omnivore. Primarily herbivore
Strength Fairly hardy fish

Food And Diet

Silver Dollar fish prefers an herbivore diet and primarily feeds on plant matter or vegetation easily found in the rivers.

However, they are not vegetarian because they will eat worms and small insects as a treat.

These are pretty convenient to pet at home aquariums as they comfortably thrive over everyday food items, such as boiled vegetables or frozen/ live small aquatics.

Food choices are not strict, and finding the proper dietary regimen can offer them a healthy lifestyle. Some food options are reported below.

  • Pellets & Flakes
  • Green vegetables such as spinach, arugula, peas, carrot, cucumber, lettuce, and potato (boiled)
  • All types of fruits in chopped form
  • Spirulina
  • Algae, seaweed, or live plants
  • Brine shrimps, bloodworms, rinsed tuna, daphnia, or tiny insects

Expert tips: These fishes are very high functioning and like running around. They can have food at least 2 – 3 times a day.    

Mannerism And Temperament

In contrast to its close relative, Piranhas, which are naturally hostile. They are highly inappropriate as tankmates. The Silver Dollar fish are pretty peaceful and friendly.

These are the best fits for community tanks and enjoy moving around the area in small groups of 5 – 6 similar species.

Sometimes, they are too shy and start behaving anxiously if kept alone or proper hiding places and covers are not provided.


These fish are preferred by aquarists specifically for commercial purposes because they do not pose any difficulty in reproductive behavior. Though it isn’t a compulsion, the Silver Dollar fish prefers to stay in groups even during mating.

Before beginning the process, you must follow specific procedures for setting up the proper environment for achieving the best results in breeding.

Fact: The Silver Dollar fish matures to reproduce at the age of twelve months when they are approximately 4 inches in length.

Water Parameters for Efficient Breeding

Though the fish is easy to breed, you can catalyze the whole process by maintaining a productive environment for them. Here is a suitable water parameter for a potential pair.

  • A pair can feel comfortable in a minimum of 40 Gallons of water, while you must increase the tank capacity if it is a group.
  • The pH of the water should be between 6.0 – 7.0, making it slightly acidic.
  • The preferred water hardness is 4 – 8 dGH.
  • The water should be slightly warm, around 26 – 29 degrees Celsius. A temperature around 32 degrees Celsius can be more beneficial in cooler regions.
  • Minimal water flow makes a soothing surrounding; thus, you can use a sponge filter.
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Note: You can choose a tank with lower heights but wide in the area for enabling long horizontal movements of the fish.

Breeding Setup

To begin with the process, you should initially select the mature pair of the species from the group and feed them with the best quality of food, preferably green vegetables, for a week.

The best pairs start showing signs that they are ready for mating. You can separate them in another tank and cover the water’s surface with green vegetation to mimic the natural conditions.

Spawning mops are helpful in breeding tanks where the eggs can safely land after spawning.

Note: You can recognize that fish is ready to mate by analyzing their fins, which appear intensely bright reddish over the corners. 


Breeding of Silver Dollar fish is usually done in small groups. As the favorable conditions are met, the male fish eventually start instigating the females for courtship.

It might be a slight forced process, and males may react hyperactively to forming a pair, but it is up to the female to choose the partner.


As the male starts to chase and flutter around the fish, the female ejects eggs into the water. These eggs sink to the surface of the substrate. Simultaneously, the male starts discharging sperm into the water, and fertilization occurs.

Fact: The Silver Dollar fish spawns around 1800 – 2200 eggs at one single stretch of the mating period. It appears almost glassy in a light golden shade.


The eggs stay safe with the parents as the adults do not act cannibalistically, but you can remove them back to the original tank as they do not care about the eggs or fry.

The fry comes out in 3 – 4 days but takes about a week to learn swimming. You can feed them with fry infusoria, followed by brine shrimp or plankton at a later stage. They will take more than six months to become adult Silver Dollar fish in size and shape.

Author’s Note: The newly born infant fish should be fed on a powdered food diet and occasionally dried, chopped vegetables.

Common Health Issues

One of the best parts about this fish is their resistance to some of the most common illnesses.

But like any other living being, the Silver Dollar fish are also susceptible to diseases but still have a high capacity to survive unhealthy conditions for longer than other species.

As in the case of every freshwater fish, a few diseases are prevalent, such as bacterial and fungal infections.

Other than infections, a widespread symptom of sickness among them is Ich, which is natural to tropic mimicking aquariums. It negatively affects the fish’s movements, weight, and urge to eat.

Ich can be diagnosed by checking the behavior of the fish and noticing random white dots on its body.

Another prominent issue is faced with scale shedding disease, where the fish are seen losing their scales. You can add aquarium salts to the tank to heal the fish with regrowth of the scales.

Managing the stress, diet, and overall hygiene of the water conditions in a tank will be crucial in preventing sickness in Silver Dollar fish.

Quick tip: If you add any artificial items to the tank, make sure to disinfect it properly to prevent any chance of disease permeation into its natural ecology.

Tank Care

Tank Care Basics
Minimum Size Of Tank 280 Litres for 6 fishes
Water Type Medium Hard Water (4 – 18 DH)
Water Temperature 75 – 82 Degrees Fahrenheit
pH Level 5.5 – 7.5
Substrate Dark sand
Lighting Dim lighting.

Optimal tank size

The Silver Dollar fish needs adequate room to swim around in the aquarium. Hence, you should avoid putting a group of these in smaller containers, as it also reduces combative interactions for food.

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Thus, with every added fish, the tank space must be increased to ensure fewer fights and more area for a school of fish to indulge in activities.

A large tank of 75–80 gallons is required for a group of 4–6 adult fish, while smaller and infant fish can be kept in a 50–55 gallon tank.

Tank Configuration

  • Plants

Green elements are an essential part of their natural habitat since they feed on the vegetation and find it a comfortable hide-out.

So, you can induce hardy and deep-rooted plants into the substrate. Some of the significant options in this category are Java Ferns, Water Sprite, Hornworts, and Java Moss.

  • Lighting

The Silver Dollar fish are not nocturnal and stay active all day. But because they are timid by nature and shy away from lights or potential attention, you must avoid using a flashlight.

You can use LEDs to create a dim-lit region that sufficiently enhances their appearance and keeps them stress-free.

  • Substrate 

These fish are accustomed to living in dark river beds and like to drill into the sand. Thus, you should prefer the substrate material, usually gravel or sand, which is of a hazy shade. The choice of a gritty substrate should be adequate for these fish.

  • Filters and Oxygen Supply

The addition of plants will provide some oxygen, but air stones or surface disturbing instruments would work even better.

So, to create agitation on the tank’s surface, you must put in a gravel filter or canister, which will keep the water clean and provide sufficient oxygen in the tank.

  • Decoration and ornamentation

These species need a lot of space to move around in schools, and unnecessary hindrances may put them under stress.

We recommend you use more living plants than anything artificial. However, some of the decorative pieces can be used, but maintain 80% free space in the tank.

Pipes, driftwood, or rocks with holes would be best for creating a hiding place.

Artificial plants can also be introduced as decoration, and the bonus is that fish would not be able to feed on them.

Water Parameters

The Silver Dollar fish is used to living in rivers, streams, or tributaries and requires fresh water because it cannot survive in salty conditions. The below-given parameters, if maintained, will ensure their healthy living.

  • The water temperature is slightly on the higher side, where these fish feel comfortable, and should be around 24 – 28 Degrees Celsius.
  • The suitable pH level is 5.5 – 7.5, which suggests a neutral to the slightly acidic water condition.
  • The water should be medium-hard, ranging from 4 – 18 gDH.

Note: Imitating tropical situations will help them sustain themselves comfortably in home aquariums.

Tank Mates

For keeping them in community tanks you must avoid small fishes, as large fishes tend to irritate small ones.

The most fundamental mates of Silver Dollar fish are themselves as they roam around in schools. But these are pretty harmonious & cordial and can happily thrive in companies of medium-sized peaceful aquatics.

Here is a list of fishes that can compatible with them.

  • Locarids
  • Rafael Catfish
  • Pimelodids
  • Arawana
  • Tin Foil Barb
  • Oscars
  • Common Plecos
  • Giant Gourami
  • Black Skirt Tetras
  • Other Silver Dollar fishes

Frequently Asked Questions

Can they live with goldfish?

You must not put them together as the Silver Dollar fish grows more extensive and can bully the small fishes by nipping their fins or may even hunt them down.

How many Silver Dollar fish can I keep in a 55-Gallon tank?

A 55 Gallons volume is smaller than the recommended tank size. Initially, you can pet 5 – 6 young fishes, but as they grow, the place is sufficient for only two of them.

Are Silver Dollar fish cichlids? 

No, these fishes are not from the Cichlid family. It belongs to the Characidae family genetically related to the Pacu fish of South America.

Do they eat fruits?

Yes, fruits and vegetables are a staple food for these fish. Try feeding them with berries, oranges, or apples.

Do they have teeth?

Contrary to their polite temperament, these fishes do have sharp teeth. In rare cases, they are observed to bite and create severe injuries to the owners or other fish.

Final Thoughts 

The Silver Dollar fish is among the most desired aquatics by fishkeepers as they look glamorous and enhance the view of the aquarium.

They present the fascinating appearance of a silver coin moving in an arrowhead shape as if flying across the plant roots.

These species are best suited for beginners in the fishkeeping industry and are profitable commercially. Acquiring additional information on water conditions, food habits, and suitable tankmates will certainly contribute positively to the improvement of its health.

About the Author

Shelby Crosby

Shelby is a passionate fishkeeper who has been writing about fish for over 5 years. She is a pro aquarist and holds a BSc Honors Degree in Wildlife and Fisheries. She creates her own beautiful aquarium layouts and loves to share her knowledge of tropical fish with other hobbyists.

Career Highlights:

  • Has worked with several aquarium manufacturers as a consultant
  • Organized and hosted workshops on freshwater fish keeping at retail stores, educational facilities, and libraries
  • Released content for the amphibian community through her writings

Educational Highlights:

  • BSc Honors in Wildlife and Fisheries in 2011 (University of Northern British Columbia)
  • Completed her undergraduate thesis on the effects of zoochlorella supplementation on the growth and health of fish.

Writing Experience

Miss Crosby is a Freelance blogger; many of her articles are posted online on various blogs. She has also written a few short articles for "Tropical Fish Hobbyist Magazine" in the past. She is a regular contributor to Her education, first-hand experience with fishkeeping, and in-depth knowledge in aquaculture make her one of the most competent writers in the industry.

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