Can cardinal tetras live with blue gouramis?

Verdict
Yes

Yes. Cardinal tetras and blue gouramis get along in the same tank. Both are fine at 76–82°F. Plan on at least 30 gal.

Cardinal tetraCardinal tetra76–84°F · pH 4.6–7 Blue gouramiBlue gourami72–82°F · pH 6–8

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 76–82°Cardinal tetra 76–84°Blue gourami 72–82°
The green band is the temperature range both can live in.
456789Both: 6–7Cardinal tetra 4.6–7Blue gourami 6–8
The green band is the pH both tolerate.

Size to scale

Cardinal tetra · 2 inBlue gourami · 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 tetraBlue gourami
Temperature76–84 °F72–82 °F
pH4.6–76–8
Adult size2.0 in5.0 in
Minimum tank20 gal30 gal
TemperamentPeacefulSemi-aggressive
Swims atMiddleTop
GroupGroups of 6+Alone or in pairs
DietOmnivoreOmnivore

Better tank mates for cardinal tetras

All cardinal tetra tank mates

Better tank mates for blue gouramis

All blue gourami tank mates

Questions

Can cardinal tetras live with blue gouramis?

Yes. Cardinal tetras and blue gouramis get along in the same tank. Both are fine at 76–82°F. Plan on at least 30 gal.

What temperature suits both cardinal tetras and blue gouramis?

76–82 °F. Cardinal tetras need 76–84 °F, blue gouramis need 72–82 °F.

What size tank do cardinal tetras and blue gouramis need together?

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