Can cardinal tetras live with arowanas?

Verdict

No. Cardinal tetras and arowanas should not share a tank. An adult silver arowana eats fish that fit in its mouth, and at 2 inches cardinal tetras do.

Cardinal tetra76–84°F · pH 4.6–7

Silver arowana75–86°F · pH 6–7

What to watch

Deal breakerAn adult silver arowana eats fish that fit in its mouth, and at 2 inches cardinal tetras do.
Deal breakerArowanas are aggressive and will bully peaceful cardinal tetras.
Watch outArowanas grow to 36 inches and need 250 gallons, far more than a tank set up for cardinal tetras.

What works

Both are fine at 76–84°F.
pH 6–7 suits both.
They use different parts of the tank: cardinal tetras the mid, arowanas the top.

Water side by side

The green band is the temperature range both can live in.

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

	Cardinal tetra	Silver arowana
Temperature	76–84 °F	75–86 °F
pH	4.6–7	6–7
Adult size	2.0 in	36.0 in
Minimum tank	20 gal	250 gal
Temperament	Peaceful	Aggressive
Swims at	Middle	Top
Group	Groups of 6+	One per tank
Diet	Omnivore	Carnivore

Better tank mates for cardinal tetras

All cardinal tetra tank mates

Questions

Can cardinal tetras live with arowanas?

No. Cardinal tetras and arowanas should not share a tank. An adult silver arowana eats fish that fit in its mouth, and at 2 inches cardinal tetras do.

What temperature suits both cardinal tetras and arowanas?

76–84 °F. Cardinal tetras need 76–84 °F, arowanas need 75–86 °F.

What size tank do cardinal tetras and arowanas need together?

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