Can bettas live with congo tetras?

Verdict
Yes

Yes, bettas and congo tetras can live together. Both are fine at 76–82°F. Plan on at least 30 gal.

BettaBetta76–82°F · pH 6.5–7.5 Congo tetraCongo tetra73–82°F · pH 6–7.5

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 76–82°Betta 76–82°Congo tetra 73–82°
The green band is the temperature range both can live in.
456789Both: 6.5–7.5Betta 6.5–7.5Congo tetra 6–7.5
The green band is the pH both tolerate.

Size to scale

Betta · 2.5 inCongo tetra · 3 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

BettaCongo tetra
Temperature76–82 °F73–82 °F
pH6.5–7.56–7.5
Adult size2.5 in3.0 in
Minimum tank5 gal30 gal
TemperamentSemi-aggressivePeaceful
Swims atTopMiddle
GroupOne per tankGroups of 6+
DietCarnivoreOmnivore

Better tank mates for bettas

All betta tank mates

Better tank mates for congo tetras

All congo tetra tank mates

Questions

Can bettas live with congo tetras?

Yes, bettas and congo tetras can live together. Both are fine at 76–82°F. Plan on at least 30 gal.

What temperature suits both bettas and congo tetras?

76–82 °F. Bettas need 76–82 °F, congo tetras need 73–82 °F.

What size tank do bettas and congo tetras need together?

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