Silver Dollar Care Guide - Aquarium Setup, Diet & Breeding

The Silver Dollar is a laterally compressed, disc-shaped characin with a bright, reflective body that gives the species its familiar name. Its silvery scales catch the light as the fish turns, while the fins may show subtle reddish, orange or dark edging depending on the individual and its condition.

These are active, peaceful shoaling fish that spend much of their time in the middle and upper levels of the aquarium. A group moving together creates an impressive display, although Silver Dollars can become nervous or skittish when kept alone or in cramped surroundings.

In nature, they are closely associated with warm, plant-rich waters and spend considerable time browsing on soft vegetation, algae and other edible plant matter. Their deep-bodied shape and strong swimming ability reflect a lifestyle in open stretches of river and flooded forest rather than among tight rock crevices.

Silver Dollars are generally peaceful community fish, but their adult size and lively swimming style make them better suited to larger aquariums than to small community setups. They are often confused with related Metynnis species, so careful identification is useful when selecting specimens.

Metynnis argenteus is native to freshwater habitats in the Amazon and adjoining river systems of South America, particularly Brazil. It inhabits slow-moving tributaries, flooded forest areas and vegetated margins where plant material is abundant.

A group of Silver Dollars needs a spacious aquarium of at least 300 litres, with a footprint around 150 cm long by 50 cm wide; a larger aquarium is preferable for a full-grown shoal. Use strong filtration, good oxygenation and a secure cover because these active characins can jump. A dark sand or fine-gravel substrate, open swimming space, driftwood and sturdy plants or artificial vegetation create a natural-looking layout. Choose tough-rooted plants or protect live plants, as Silver Dollars commonly nibble soft foliage, and leave clear areas for the group to swim together.

Up to about 14 cm (5.5 in) in total length. Females are often slightly deeper-bodied and may be marginally larger than males.

Silver Dollars are predominantly herbivorous and should receive a diet centred on high-quality algae wafers, spirulina-based foods and vegetable matter. Offer blanched spinach, lettuce, peas, courgette or cucumber alongside a good staple flake or pellet, with occasional additions of bloodworm, brine shrimp or other meaty foods to provide variety. Feed modest portions that are consumed promptly, while ensuring every fish gets access to food in the group.

Silver Dollars suit peaceful community aquariums containing similarly sized, robust fish. Suitable companions can include larger tetras, peaceful barbs, rainbowfish, larger rasboras, peaceful South American cichlids such as angelfish, and compatible bottom dwellers including medium to large Corydoras and peaceful plecos. Avoid very small fish that may be intimidated or accidentally swallowed, slow long-finned species, aggressive cichlids and fin-nipping tankmates. Silver Dollars may also eat soft-leaved live plants, so plant-eating should be considered when planning the community.

Silver Dollars are egg-scattering characins that can be bred in a spacious, softly lit breeding aquarium with clean, slightly acidic to neutral water and fine-leaved plants or spawning mops. Condition a group with plentiful vegetable foods and live or frozen foods, then introduce the fish when the females are full of eggs. Spawning usually takes place among plants, with the eggs scattered across the aquarium floor and foliage. The adults should be removed after spawning because they may eat the eggs; eggs generally hatch within a few days, and the fry require very small foods such as infusoria before moving on to newly hatched brine shrimp.

Females are usually fuller-bodied, particularly when carrying eggs, while mature males tend to be slightly slimmer and may develop more extended dorsal and anal fins with stronger reddish or darker coloration. These differences can be subtle outside breeding condition.