Goldfish (Carassius auratus) is a beginner-care freshwater species. Minimum tank: 20 gallons (single fancy). Adult size: 6-12 inches. Diet: omnivore. Lifespan: 10-30 years. Hardy, tolerates parameter swings within reason, and accepts a wide variety of food. A first-time aquarist can succeed with this species in a properly cycled tank. Browse Goldfish care guide for the full breakdown including water parameters, tankmate compatibility, and feeding schedule.
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