Tank Setup
- Tank size: 55 gallons minimum for a school of 5. 75+ is better — they are active swimmers that grow to 6 inches.
- Plants: DO NOT USE LIVE PLANTS. Silver dollars are voracious herbivores that will eat every plant within days. Use artificial plants or leave the tank unplanted.
- Decor: Driftwood, rocks, and artificial plants for cover
- Lid: Essential — silver dollars are skittish and jump when startled
Water Parameters
- Temperature: 75–82°F
- pH: 5.5–7.5 (slightly acidic preferred)
- GH: 4–15 dGH
Diet & Feeding
Primarily herbivorous — one of the few truly plant-eating aquarium fish:
- Staple: Spirulina flakes, algae wafers
- Vegetables: Blanched lettuce, spinach, peas, zucchini — they devour these
- Supplements: Occasional frozen bloodworms or brine shrimp for protein
Tank Mates
Despite being related to piranhas, silver dollars are completely peaceful. Their large size and open-water swimming makes them excellent companions for large cichlids — their calm presence as "dither fish" actually reduces cichlid aggression. Compatible with oscars, Jack Dempseys, firemouths, large barbs, and other robust species.
Frequently Asked Questions
Are silver dollars related to piranhas?
Yes — they are in the same family (Serrasalmidae). However, silver dollars are entirely herbivorous and completely harmless. Think of them as the "vegetarian piranhas."
Will silver dollars eat my plants?
Absolutely. Every single one. They are among the most destructive plant-eaters in the freshwater hobby. Do not put live plants in a silver dollar tank.