Can cardinal tetras live with swordtails?

Verdict

Yes, with care

Yes, with care. Cardinal tetras and swordtails can share a tank, but watch one thing. Water chemistry is a squeeze. The only pH that suits both is around 7.

Cardinal tetra76–84°F · pH 4.6–7

Swordtail72–79°F · pH 7–8.3

What to watch

Watch outWater chemistry is a squeeze. The only pH that suits both is around 7.

What works

Both are fine at 76–79°F.

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	Swordtail
Temperature	76–84 °F	72–79 °F
pH	4.6–7	7–8.3
Adult size	2.0 in	5.0 in
Minimum tank	20 gal	30 gal
Temperament	Peaceful	Semi-aggressive
Swims at	Middle	Middle
Group	Groups of 6+	Groups of 3+
Diet	Omnivore	Omnivore

Better tank mates for cardinal tetras

All cardinal tetra tank mates

Better tank mates for swordtails

All swordtail tank mates

Questions

Can cardinal tetras live with swordtails?

Yes, with care. Cardinal tetras and swordtails can share a tank, but watch one thing. Water chemistry is a squeeze. The only pH that suits both is around 7.

What temperature suits both cardinal tetras and swordtails?

76–79 °F. Cardinal tetras need 76–84 °F, swordtails need 72–79 °F.

What size tank do cardinal tetras and swordtails need together?

At least 30 gal, set by the swordtail. Add space for each extra fish.