Overview
The Goldfish (Carassius auratus) is a freshwater fish belonging to the family Cyprinidae. It thrives at temperatures of 10–22 °C with a pH of 6.5–8.5, and requires a minimum tank volume of 150 litres. Known for its peaceful community fish; produces significant waste, it is considered a beginner-level species. A cold-water species that does not belong in tropical tanks; powerful filtration is essential. Water changes of 25–30 % weekly, stable parameters, and appropriate tank mates are key to long-term success with this species.
Scientific Classification
| Rank | Classification |
|---|---|
| Family | Cyprinidae |
| Genus | Carassius |
| Species | Carassius auratus |
| Water type | freshwater |
| Native range | Reunion|Caribbean|Middle America|North America|Oceania|Southern Asia|Zeeschelde|North Pacific Ocean|North East Pacific|Pacific, Northeast|The Coastal Waters of Southeast Alaska and British Columbia|Kenya|Serbia |
Natural Habitat
Carassius auratus originates from Reunion|Caribbean|Middle America|North America|Oceania|Southern Asia|Zeeschelde|North Pacific Ocean|North East Pacific|P. It inhabits freshwater environments and is adapted to the water conditions found in its native range.
Appearance
Adults reach 15–30 cm (fancy varieties smaller) in length. The body is freshwater and the species displays characteristic coloration suited to its environment.
Behavior
This species is described as a peaceful community fish; produces significant waste. It does not school and can be kept individually or in small numbers. Activity level is moderate. A cold-water species that does not belong in tropical tanks; powerful filtration is essential.
| Trait | Value |
|---|---|
| Temperament | peaceful community fish; produces significant waste |
| Schooling | No |
| Activity level | moderate |
Water Requirements
| Parameter | Ideal Range | Notes |
|---|---|---|
| Temperature | 10–22°C (50–72°F) | Use a reliable adjustable heater |
| pH | 6.5–8.5 | Avoid sudden swings |
| Hardness (GH) | 5–25 dGH dGH | Soft to moderately hard |
| Ammonia | 0 ppm | Any detectable ammonia signals a problem |
| Nitrite | 0 ppm | Toxic even at low levels |
| Nitrate | <20 ppm | Manage through regular partial water changes |
| Min. tank | 150L (40 gal) | Larger tanks are easier to keep stable |
Interesting Facts
- Goldfish have a digestive system, not a stomach — they should be fed small amounts frequently.
- The common goldfish is derived from wild Prussian Carp (Carassius gibelio) domesticated in China over 1,000 years ago.
- Goldfish can live over 20 years in proper conditions; most die early due to inadequate tank size.
📋 Full Care Guide
Ready to set up a tank for your Goldfish? The complete care guide covers tank setup, feeding schedule, common diseases, tank mates, and breeding.
Read Goldfish Care Guide →Related Species
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This species profile was reviewed for biological accuracy and practical aquarium care guidance. For suspected illness or disease, test your water parameters first and consult an aquatic veterinarian if symptoms persist.