Silver Dollar

Care at a glance

Overview

Keep them in a school of five or more in a large tank of at least 265 liters, since a lone fish stays stressed and stays hidden. They are active mid and upper swimmers and are mostly peaceful with fish too big to swallow. Feed mainly greens: vegetable flakes, spirulina, and fresh produce like spinach or lettuce, with protein foods only occasionally. They prefer soft to neutral, warm water.

In the wild

This silver dollar comes from rivers and streams in Brazil's Amazon basin, in warm, soft, slightly acidic water shaded by overhanging plants. Those conditions point to a planted-edge setup with soft to neutral water and a temperature in the mid to high 20s C. Keep in mind they graze on plants, so use tough species or expect them to be eaten. Open mid-water space matters more than heavy decor.

Good to know

Metynnis argenteus is a characin in the family Characidae, with a tall, round, silver body that gives it its name. Adults reach about 15 cm. It scatters eggs and does not guard them, and home breeding is hard. The closely related Metynnis hypsauchen is often sold under the same name and looks nearly identical.

Did you know

Silver dollars are heavy plant eaters, so much so that aquarists treat almost any live planting as temporary. In the wild that grazing helps keep aquatic vegetation in check and moves nutrients through the system.

Related species

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  Silver Dollar

  Metynnis hypsauchen

  5.5 in (14 cm)70 gal (265 L)75–82°F (24–28°C)

• 

  Buenos Aires tetra

  Hyphessobrycon anisitsi

  3 in (7.5 cm)25 gal (95 L)66–81°F (19–27°C)

• 

  Red eye tetra

  Moenkhausia sanctaefilomenae

  2.8 in (7 cm)28 gal (105 L)72–79°F (22–26°C)

• 

  Blind cave tetra

  Astyanax mexicanus

  4.7 in (12 cm)25 gal (95 L)70–77°F (21–25°C)

• 

  Bucktooth tetra

  Exodon paradoxus

  4.7 in (12 cm)45 gal (170 L)73–82°F (23–28°C)

• 

  Black widow tetra

  Gymnocorymbus ternetzi

  2.4 in (6 cm)20 gal (75 L)68–79°F (20–26°C)