Can a fancy goldfish live with common goldfish?
Edited by Marin Hale · last reviewed October 29, 2026
Sometimes, with care.
Common goldfish are fast and outcompete slow fancy goldfish for food, and they grow much larger. Most keepers house them separately.
Plan on a tank of at least 75 gallons for both.
By tank size
| 5 gal | 10 gal | 20 gal | 29 gal | 40 gal | 55 gal | 75 gal |
|---|---|---|---|---|---|---|
| No | No | No | No | No | No | Maybe |
Below 75 gallons there isn’t enough room for both, so the answer is no.
How to try it
Use a 75-gallon tank as the absolute minimum, since that's what the common goldfish needs, and keep the water at 65–74°F so both are comfortable. Keep at least 2 common goldfish together, add fancy goldfish only to a mature, cycled tank, and use sturdy plants or hiding spots so slower fancies can get away from the faster commons.
- Make sure the 75-gallon tank is fully cycled and the water sits at 65–74°F with pH between 7.0 and 8.4.
- Start with a group of at least 2 common goldfish if you don't already have them, and let them settle in.
- Add the fancy goldfish only after the tank is mature, ideally when the commons are not at their most food-driven.
- Put a few sinking pellets in the bottom area, away from where the commons feed, so the bottom-dwelling fancies get their share.
- Feed in two spots at once: scatter some food near the surface to draw the commons away while the fancies eat at the bottom.
Warning signs in the first weeks
- Fancy goldfish hang back or are always empty-handed at feeding time while the common goldfish take the food first.
- A fancy goldfish looks thinner than its tankmates after the first couple of weeks.
- Common goldfish chase or crowd a fancy goldfish, or a fancy hides constantly and stops exploring the tank.
- Torn or clamped fins, or a fancy goldfish that sits listlessly near the bottom or in a corner.
Backup plan: If the fancies are being outcompeted for food or stressed, separate the two types into their own tanks, since most keepers house them apart. Remember that common goldfish grow to 8–12 inches and need the 75-gallon minimum, so plan their housing accordingly.
How we reached this verdict
| Pass | Water temperature | Both are comfortable at 65–74°F. |
|---|---|---|
| Pass | pH | Both are comfortable at pH 7.0–8.4. |
| Pass | Size and appetite | Neither is small enough to be eaten by the other. |
| Pass | Fins | No fin-nipping risk. |
| Watch | Temperament | Common goldfish are fast and outcompete slow fancy goldfish for food, and they grow much larger. Most keepers house them separately. Known behavior, from hobbyist experience rather than the data rules. |
Side by side
| Trait | Fancy goldfish | Common goldfish |
|---|---|---|
| Tolerates | 65–74°F (18–23°C) | 60–74°F (16–23°C) |
| pH | 6.8–8.4 | 7–8.4 |
| Adult size | 6–8 in | 8–12 in |
| Temperament | Peaceful | Peaceful |
| Smallest tank | 20 gallons (76 L) | 75 gallons (284 L) |
| Keep at least | — | 2 together |
| Swims | Bottom | — |
Better tank mates for a fancy goldfish
Verdicts come from cross-checked species data and our compatibility rules. How verdicts work · Common goldfish care