Can cardinal tetras live with dwarf neon rainbowfish?

Verdict
Yes

Yes, cardinal tetras and dwarf neon rainbowfish can live together. Both are fine at 76–82°F. Plan on at least 20 gal.

Cardinal tetraCardinal tetra76–84°F · pH 4.6–7 Dwarf neon rainbowfishDwarf neon rainbowfish75–82°F · pH 6.5–7.5

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 76–82°Cardinal tetra 76–84°Dwarf neon rainbowfish 75–82°
The green band is the temperature range both can live in.
456789Both: 6.5–7Cardinal tetra 4.6–7Dwarf neon rainbowfish 6.5–7.5
The green band is the pH both tolerate.

Size to scale

Cardinal tetra · 2 inDwarf neon rainbowfish · 2.5 in0"1"2"3"4"5"6"
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 tetraDwarf neon rainbowfish
Temperature76–84 °F75–82 °F
pH4.6–76.5–7.5
Adult size2.0 in2.5 in
Minimum tank20 gal20 gal
TemperamentPeacefulPeaceful
Swims atMiddleMiddle
GroupGroups of 6+Groups of 6+
DietOmnivoreOmnivore

Better tank mates for cardinal tetras

All cardinal tetra tank mates

Better tank mates for dwarf neon rainbowfish

All dwarf neon rainbowfish tank mates

Questions

Can cardinal tetras live with dwarf neon rainbowfish?

Yes, cardinal tetras and dwarf neon rainbowfish can live together. Both are fine at 76–82°F. Plan on at least 20 gal.

What temperature suits both cardinal tetras and dwarf neon rainbowfish?

76–82 °F. Cardinal tetras need 76–84 °F, dwarf neon rainbowfish need 75–82 °F.

What size tank do cardinal tetras and dwarf neon rainbowfish need together?

At least 20 gal, set by the cardinal tetra. Add space for each extra fish.