Can fancy goldfish live with arowanas?

Verdict

No. Fancy goldfish and arowanas should not share a tank. Fancy goldfish are coldwater animals (65–74°F); arowanas need 75–86°F. No temperature suits both.

Fancy goldfish65–74°F · pH 7–8

Silver arowana75–86°F · pH 6–7

What to watch

Deal breakerFancy goldfish are coldwater animals (65–74°F); arowanas need 75–86°F. No temperature suits both.
Deal breakerAn adult silver arowana eats fish that fit in its mouth, and at 6 inches fancy goldfish do.
Deal breakerArowanas are aggressive and will bully peaceful fancy goldfish.
Watch outWater chemistry is a squeeze. The only pH that suits both is around 7.
Watch outArowanas grow to 36 inches and need 250 gallons, far more than a tank set up for fancy goldfish.

Water side by side

The ranges do not meet, so one of them would always be too warm or too cold.

The green band is the pH both tolerate.

Size to scale

Adult length in an aquarium. A fish can swallow anything that fits in its mouth, roughly a third to half its own length for predators.

Care at a glance

	Fancy goldfish	Silver arowana
Temperature	65–74 °F	75–86 °F
pH	7–8	6–7
Adult size	6.0 in	36.0 in
Minimum tank	30 gal	250 gal
Temperament	Peaceful	Aggressive
Swims at	All levels	Top
Group	Alone or in pairs	One per tank
Diet	Omnivore	Carnivore

Better tank mates for fancy goldfish

All fancy goldfish tank mates

Questions

Can fancy goldfish live with arowanas?

No. Fancy goldfish and arowanas should not share a tank. Fancy goldfish are coldwater animals (65–74°F); arowanas need 75–86°F. No temperature suits both.

What temperature suits both fancy goldfish and arowanas?

None. Fancy goldfish need 65–74 °F and arowanas need 75–86 °F, so the ranges do not meet.

What size tank do fancy goldfish and arowanas need together?

At least 250 gal, set by the silver arowana. Add space for each extra fish.