Aquariumgoldfish · freshwater
Fancy Goldfish: adult size, tank size & tankmates
The Fancy Goldfish (Carassius auratus (fancy varieties)) grows to about 8 in (20.3 cm TL). It needs a tank at least about 30 gallons. It doesn't need a group of its own kind, at 50–70°F.
How big it really gets
Drawn to scale against common tank lengths. Green bars meet the minimum tank length from our sources.
Outgrows most home tanks. Routinely sold for bowls and small tanks; needs 20-30+ gal and heavy filtration.
Will it fit your tank?
Quick facts
- Adult size
- 8 in (20.3 cm TL)
- Minimum tank
- about 30 gallons
- Temperature
- 50–70°F
- pH
- 6.5–7.5
- Hardness
- 5–19 dGH
- Group size
- 1 (solitary or pair)
- With other fish
- peaceful
- With its own kind
- peaceful
- Swims
- middle of the tank
- Diet
- omnivore
- Care level
- intermediate
- Lifespan
- not stated in sources
Watch for: long fins that nippers target · eats small fish · eats shrimp · eats live plants
Fancy Goldfish tankmates
Checked with the same rules as our tank builder: temperature overlap, pH and hardness, predation and mouth size, fin-nipping and temperament. Tank size is left out here; check it in the builder.
Good tankmates
- Cherry BarbAdult ~2.4 in · 68–81°F
- Lemon TetraAdult ~1.9 in · 68–82°F
- GuppyAdult ~2.8 in · 63–82°F
- PlatyAdult ~2.4 in · 68–79°F
- SwordtailNeeds careAdult ~6.6 in · 61–82°F
- White Cloud Mountain MinnowNeeds careAdult ~1.9 in · 57–72°F
- Paradise FishNeeds careAdult ~3.8 in · 50–72°F
- Rosy BarbAdult ~4.7 in · 61–75°F
- Gold BarbAdult ~3.5 in · 61–75°F
- Pearl DanioAdult ~2.6 in · 61–77°F
Use caution
- Harlequin RasboraFancy Goldfish and Harlequin Rasbora only share 70–70°F. That's a tight window.
- Bronze CoryFancy Goldfish and Bronze Cory only share 70–70°F. That's a tight window.
- Kuhli LoachFancy Goldfish and Kuhli Loach only share 70–70°F. That's a tight window.
- Bristlenose PlecoFancy Goldfish and Bristlenose Pleco only share 70–70°F. That's a tight window.
- OtocinclusNeeds careFancy Goldfish and Otocinclus only share 70–70°F. That's a tight window.
- Mystery SnailFancy Goldfish and Mystery Snail only share 70–70°F. That's a tight window.
- Zebra DanioNeeds careZebra Danio nips fins, and Fancy Goldfish has long fins.
- Tiger BarbNeeds careTiger Barb nips fins, and Fancy Goldfish has long fins.
Avoid
- Neon TetraFancy Goldfish and Neon Tetra only share 70–70°F. That's a tight window.
- Cardinal TetraFancy Goldfish (50–70°F) and Cardinal Tetra (73–84°F) need different temperatures.
- Ember TetraFancy Goldfish eats small fish, and Ember Tetra only grows to about 0.9 in.
- Chili RasboraFancy Goldfish eats small fish, and Chili Rasbora only grows to about 0.9 in.
- Celestial Pearl DanioFancy Goldfish eats small fish, and Celestial Pearl Danio only grows to about 1 in.
- Rummy-nose TetraFancy Goldfish (50–70°F) and Rummy-nose Tetra (73–79°F) need different temperatures.
- Black Neon TetraFancy Goldfish (50–70°F) and Black Neon Tetra (73–82°F) need different temperatures.
- Glowlight TetraFancy Goldfish (50–70°F) and Glowlight Tetra (75–82°F) need different temperatures.
All 105 species we checked against the Fancy Goldfish
| Species | Verdict | Why |
|---|---|---|
| Bala Shark | Compatible | No conflicts found |
| Cherry Barb | Compatible | No conflicts found |
| Common / Comet Goldfish | Compatible | No conflicts found |
| Denison Barb | Compatible | No conflicts found |
| Firemouth Cichlid | Compatible | No conflicts found |
| Giant Danio | Compatible | No conflicts found |
| Glass Catfish | Compatible | No conflicts found |
| Gold Barb | Compatible | No conflicts found |
| Guppy | Compatible | No conflicts found |
| Hillstream Loach | Compatible | No conflicts found |
| Japanese Trapdoor Snail | Compatible | No conflicts found |
| Lemon Tetra | Compatible | No conflicts found |
| Marbled Hatchetfish | Compatible | No conflicts found |
| Odessa Barb | Compatible | No conflicts found |
| Paradise Fish | Compatible | No conflicts found |
| Pearl Danio | Compatible | No conflicts found |
| Platy | Compatible | No conflicts found |
| Rainbow Shark | Compatible | No conflicts found |
| Red-Tail Shark | Compatible | No conflicts found |
| Rosy Barb | Compatible | No conflicts found |
| Siamese Algae Eater | Compatible | No conflicts found |
| Silver Hatchetfish | Compatible | No conflicts found |
| Swordtail | Compatible | No conflicts found |
| Variatus Platy | Compatible | No conflicts found |
| Weather Loach | Compatible | No conflicts found |
| White Cloud Mountain Minnow | Compatible | No conflicts found |
| Black Skirt Tetra | Caution | Black Skirt Tetra nips fins, and Fancy Goldfish has long fins. |
| Bleeding Heart Tetra | Caution | Fancy Goldfish and Bleeding Heart Tetra only share 70–70°F. That's a tight window. |
| Bristlenose Pleco | Caution | Fancy Goldfish and Bristlenose Pleco only share 70–70°F. That's a tight window. |
| Bronze Cory | Caution | Fancy Goldfish and Bronze Cory only share 70–70°F. That's a tight window. |
| Buenos Aires Tetra | Caution | Buenos Aires Tetra nips fins, and Fancy Goldfish has long fins. |
| Common Pleco | Caution | Fancy Goldfish and Common Pleco only share 70–70°F. That's a tight window. |
| Harlequin Rasbora | Caution | Fancy Goldfish and Harlequin Rasbora only share 70–70°F. That's a tight window. |
| Kuhli Loach | Caution | Fancy Goldfish and Kuhli Loach only share 70–70°F. That's a tight window. |
| Malaysian Trumpet Snail | Caution | Fancy Goldfish and Malaysian Trumpet Snail only share 70–70°F. That's a tight window. |
| Molly | Caution | Fancy Goldfish and Molly only share 70–70°F. That's a tight window. |
| Mystery Snail | Caution | Fancy Goldfish and Mystery Snail only share 70–70°F. That's a tight window.; Fancy Goldfish (pH 6.5–7.5) and Mystery Snail (pH unknown) prefer different pH. |
| Otocinclus | Caution | Fancy Goldfish and Otocinclus only share 70–70°F. That's a tight window. |
| Serpae Tetra | Caution | Serpae Tetra nips fins, and Fancy Goldfish has long fins. |
| Tiger Barb | Caution | Tiger Barb nips fins, and Fancy Goldfish has long fins. |
| Yoyo Loach | Caution | Yoyo Loach nips fins, and Fancy Goldfish has long fins. |
| Zebra Danio | Caution | Zebra Danio nips fins, and Fancy Goldfish has long fins. |
| African Dwarf Frog | Avoid | Fancy Goldfish (50–70°F) and African Dwarf Frog (74–77°F) need different temperatures.; Fancy Goldfish eats small fish, and African Dwarf Frog only grows to about 1.4 in. |
| Amano Shrimp | Avoid | Fancy Goldfish and Amano Shrimp only share 70–70°F. That's a tight window.; Fancy Goldfish will eat Amano Shrimp. |
| Angelfish | Avoid | Fancy Goldfish (50–70°F) and Angelfish (75–86°F) need different temperatures. |
| Assassin Snail | Avoid | Fancy Goldfish (50–70°F) and Assassin Snail (75–80°F) need different temperatures. |
| Bamboo Shrimp | Avoid | Fancy Goldfish (50–70°F) and Bamboo Shrimp (71–82°F) need different temperatures.; Fancy Goldfish will eat Bamboo Shrimp. |
| Betta | Avoid | Fancy Goldfish (50–70°F) and Betta (72–86°F) need different temperatures. |
| Black Neon Tetra | Avoid | Fancy Goldfish (50–70°F) and Black Neon Tetra (73–82°F) need different temperatures. |
| Blood Parrot Cichlid | Avoid | Fancy Goldfish (50–70°F) and Blood Parrot Cichlid (76–80°F) need different temperatures. |
| Boesemani Rainbowfish | Avoid | Fancy Goldfish (50–70°F) and Boesemani Rainbowfish (81–86°F) need different temperatures. |
| Bolivian Ram | Avoid | Fancy Goldfish (50–70°F) and Bolivian Ram (75–82°F) need different temperatures. |
| Bumblebee Goby | Avoid | Fancy Goldfish (50–70°F) and Bumblebee Goby (72–82°F) need different temperatures. |
| Cardinal Tetra | Avoid | Fancy Goldfish (50–70°F) and Cardinal Tetra (73–84°F) need different temperatures. |
| Celestial Pearl Danio | Avoid | Fancy Goldfish eats small fish, and Celestial Pearl Danio only grows to about 1 in. |
| Cherry Shrimp | Avoid | Fancy Goldfish will eat Cherry Shrimp. |
| Chili Rasbora | Avoid | Fancy Goldfish eats small fish, and Chili Rasbora only grows to about 0.9 in. |
| Chinese Algae Eater | Avoid | Fancy Goldfish (50–70°F) and Chinese Algae Eater (72–79°F) need different temperatures.; Chinese Algae Eater is aggressive toward tankmates. Fancy Goldfish is peaceful. |
| Clown Killifish | Avoid | Fancy Goldfish eats small fish, and Clown Killifish only grows to about 1.6 in. |
| Clown Loach | Avoid | Fancy Goldfish (50–70°F) and Clown Loach (75–86°F) need different temperatures. |
| Clown Pleco | Avoid | Fancy Goldfish (50–70°F) and Clown Pleco (73–82°F) need different temperatures. |
| Cockatoo Dwarf Cichlid | Avoid | Fancy Goldfish (50–70°F) and Cockatoo Dwarf Cichlid (72–84°F) need different temperatures.; Fancy Goldfish (pH 6.5–7.5) and Cockatoo Dwarf Cichlid (pH 5–6) prefer different pH. |
| Congo Tetra | Avoid | Fancy Goldfish (50–70°F) and Congo Tetra (73–82°F) need different temperatures. |
| Convict Cichlid | Avoid | Fancy Goldfish (50–70°F) and Convict Cichlid (75–82°F) need different temperatures.; Convict Cichlid nips fins, and Fancy Goldfish has long fins. |
| Crystal Red Shrimp | Avoid | Fancy Goldfish (50–70°F) and Crystal Red Shrimp (71–76°F) need different temperatures.; Fancy Goldfish will eat Crystal Red Shrimp. |
| Diamond Tetra | Avoid | Fancy Goldfish (50–70°F) and Diamond Tetra (75–82°F) need different temperatures.; Diamond Tetra nips fins, and Fancy Goldfish has long fins. |
| Discus | Avoid | Fancy Goldfish (50–70°F) and Discus (79–86°F) need different temperatures. |
| Dwarf Gourami | Avoid | Fancy Goldfish (50–70°F) and Dwarf Gourami (72–81°F) need different temperatures. |
| Dwarf Neon Rainbowfish | Avoid | Fancy Goldfish (50–70°F) and Dwarf Neon Rainbowfish (72–82°F) need different temperatures. |
| Electric Blue Acara | Avoid | Fancy Goldfish (50–70°F) and Electric Blue Acara (72–82°F) need different temperatures. |
| Electric Yellow Lab | Avoid | Fancy Goldfish (50–70°F) and Electric Yellow Lab (75–82°F) need different temperatures.; Electric Yellow Lab nips fins, and Fancy Goldfish has long fins. |
| Ember Tetra | Avoid | Fancy Goldfish eats small fish, and Ember Tetra only grows to about 0.9 in. |
| Endler's Livebearer | Avoid | Fancy Goldfish (50–70°F) and Endler's Livebearer (75–86°F) need different temperatures.; Fancy Goldfish eats small fish, and Endler's Livebearer only grows to about 1.2 in. |
| Forktail Blue-eye | Avoid | Fancy Goldfish (50–70°F) and Forktail Blue-eye (75–82°F) need different temperatures. |
| German Blue Ram | Avoid | Fancy Goldfish (50–70°F) and German Blue Ram (81–86°F) need different temperatures. |
| Ghost Shrimp | Avoid | Fancy Goldfish (50–70°F) and Ghost Shrimp (72–82°F) need different temperatures.; Fancy Goldfish will eat Ghost Shrimp. |
| Glowlight Tetra | Avoid | Fancy Goldfish (50–70°F) and Glowlight Tetra (75–82°F) need different temperatures. |
| Head-and-tail-light Tetra | Avoid | Fancy Goldfish (50–70°F) and Head-and-tail-light Tetra (75–82°F) need different temperatures. |
| Honey Gourami | Avoid | Fancy Goldfish (50–70°F) and Honey Gourami (72–81°F) need different temperatures. |
| Iridescent Shark | Avoid | Fancy Goldfish (50–70°F) and Iridescent Shark (72–79°F) need different temperatures. |
| Julii Cory | Avoid | Fancy Goldfish (50–70°F) and Julii Cory (72–79°F) need different temperatures. |
| Kissing Gourami | Avoid | Fancy Goldfish (50–70°F) and Kissing Gourami (72–86°F) need different temperatures. |
| Kribensis | Avoid | Fancy Goldfish (50–70°F) and Kribensis (75–81°F) need different temperatures. |
| Lambchop Rasbora | Avoid | Fancy Goldfish (50–70°F) and Lambchop Rasbora (73–82°F) need different temperatures.; Fancy Goldfish eats small fish, and Lambchop Rasbora only grows to about 1.4 in. |
| Moonlight Gourami | Avoid | Fancy Goldfish (50–70°F) and Moonlight Gourami (77–86°F) need different temperatures. |
| Neon Tetra | Avoid | Fancy Goldfish and Neon Tetra only share 70–70°F. That's a tight window.; Fancy Goldfish eats small fish, and Neon Tetra only grows to about 1.4 in. |
| Nerite Snail | Avoid | Fancy Goldfish (50–70°F) and Nerite Snail (72–78°F) need different temperatures.; Fancy Goldfish (pH 6.5–7.5) and Nerite Snail (pH 8–8.4) prefer different pH. |
| Oscar | Avoid | Fancy Goldfish (50–70°F) and Oscar (72–82°F) need different temperatures.; Oscar can bully smaller, peaceful Fancy Goldfish. |
| Panda Cory | Avoid | Fancy Goldfish (50–70°F) and Panda Cory (72–77°F) need different temperatures. |
| Pea Puffer | Avoid | Fancy Goldfish (50–70°F) and Pea Puffer (72–82°F) need different temperatures.; Fancy Goldfish eats small fish, and Pea Puffer only grows to about 1.4 in. |
| Pearl Gourami | Avoid | Fancy Goldfish (50–70°F) and Pearl Gourami (75–86°F) need different temperatures. |
| Penguin Tetra | Avoid | Fancy Goldfish (50–70°F) and Penguin Tetra (72–82°F) need different temperatures.; Penguin Tetra nips fins, and Fancy Goldfish has long fins. |
| Peppered Cory | Avoid | Fancy Goldfish (50–70°F) and Peppered Cory (72–79°F) need different temperatures. |
| Pictus Catfish | Avoid | Fancy Goldfish (50–70°F) and Pictus Catfish (72–77°F) need different temperatures. |
| Pristella Tetra | Avoid | Fancy Goldfish (50–70°F) and Pristella Tetra (72–82°F) need different temperatures. |
| Pygmy Cory | Avoid | Fancy Goldfish (50–70°F) and Pygmy Cory (72–79°F) need different temperatures.; Fancy Goldfish eats small fish, and Pygmy Cory only grows to about 1.4 in. |
| Ramshorn Snail | Avoid | Fancy Goldfish (50–70°F) and Ramshorn Snail (72–82°F) need different temperatures. |
| Rummy-nose Tetra | Avoid | Fancy Goldfish (50–70°F) and Rummy-nose Tetra (73–79°F) need different temperatures. |
| Scissortail Rasbora | Avoid | Fancy Goldfish (50–70°F) and Scissortail Rasbora (72–77°F) need different temperatures. |
| Silver Tip Tetra | Avoid | Fancy Goldfish (50–70°F) and Silver Tip Tetra (73–82°F) need different temperatures.; Silver Tip Tetra nips fins, and Fancy Goldfish has long fins. |
| Sparkling Gourami | Avoid | Fancy Goldfish (50–70°F) and Sparkling Gourami (72–82°F) need different temperatures. |
| Sterbai Cory | Avoid | Fancy Goldfish (50–70°F) and Sterbai Cory (75–82°F) need different temperatures. |
| Three-spot Gourami | Avoid | Fancy Goldfish (50–70°F) and Three-spot Gourami (75–86°F) need different temperatures. |
| Tinfoil Barb | Avoid | Fancy Goldfish (50–70°F) and Tinfoil Barb (72–77°F) need different temperatures. |
| Upside-down Catfish | Avoid | Fancy Goldfish (50–70°F) and Upside-down Catfish (75–82°F) need different temperatures. |
Care notes
Needs: Coldwater, usually no heater; heavy waste so strong filtration and large water volume; slow swimmers that cannot escape pestering or nippy fish; digs and eats soft plants (Co-Op suggests anubias/ferns on wood or rock)
Group: No source states a minimum group; FKW: best kept with own kind or other peaceful goldfish; Co-Op: 20 gal for the first goldfish plus at least 10 gal per additional fish
Temperament: peaceful toward other fish, peaceful toward its own kind. Lives in the middle of the tank.
Common questions
How big does a Fancy Goldfish get?
About 8 inches (20.3 cm TL) as an adult, according to fishkeepingworld.com.
What size tank does a Fancy Goldfish need?
At least about 30 gallons. The smallest standard tank that meets that is a 40 gallon breeder.
How many Fancy Goldfishs should be kept together?
It can be kept on its own. No source states a minimum group; FKW: best kept with own kind or other peaceful goldfish; Co-Op: 20 gal for the first goldfish plus at least 10 gal per additional fish
What fish can live with a Fancy Goldfish?
Species that passed every check include Cherry Barb, Lemon Tetra, Guppy, Platy, Swordtail, White Cloud Mountain Minnow.
Gear for a Fancy Goldfish setup
TankSmallest standard tank that meets its minimum: 40 gallon breeder (36 in long).Find on Amazon →ThermometerCool-water fish: skip the heater, watch summer highs.Find on Amazon →DriftwoodGrazing wood and biofilm are part of its diet.Find on Amazon →FoodA quality flake or micro-pellet as a staple.Find on Amazon →Test kitCheck ammonia, nitrite and pH. Cycle the tank before adding fish.Find on Amazon →
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Related guides
Sources
Values come from these pages, in our own words. Status: verified (independent spot-check). Last reviewed 2026-10-12.
- fishkeepingworld.com /fancy-goldfish/
- chewy.com /education/fish/goldfish/what-size-goldfish-tank-do-i-need
- fishbase.se /summary/Carassius-auratus.html
- nas.er.usgs.gov /queries/FactSheet.aspx?speciesID=508
- aquariumcoop.com /blogs/aquarium/goldfish-care-guide