Can congo tetras live with black neon tetras?

Verdict
Yes

Yes, congo tetras and black neon tetras can live together. Both are fine at 73–81°F. Plan on at least 30 gal.

Congo tetraCongo tetra73–82°F · pH 6–7.5 Black neon tetraBlack neon tetra73–81°F · pH 5.5–7.5

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 73–81°Congo tetra 73–82°Black neon tetra 73–81°
The green band is the temperature range both can live in.
456789Both: 6–7.5Congo tetra 6–7.5Black neon tetra 5.5–7.5
The green band is the pH both tolerate.

Size to scale

Congo tetra · 3 inBlack neon tetra · 1.5 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

Congo tetraBlack neon tetra
Temperature73–82 °F73–81 °F
pH6–7.55.5–7.5
Adult size3.0 in1.5 in
Minimum tank30 gal15 gal
TemperamentPeacefulPeaceful
Swims atMiddleMiddle
GroupGroups of 6+Groups of 6+
DietOmnivoreOmnivore

Better tank mates for congo tetras

All congo tetra tank mates

Better tank mates for black neon tetras

All black neon tetra tank mates

Questions

Can congo tetras live with black neon tetras?

Yes, congo tetras and black neon tetras can live together. Both are fine at 73–81°F. Plan on at least 30 gal.

What temperature suits both congo tetras and black neon tetras?

73–81 °F. Congo tetras need 73–82 °F, black neon tetras need 73–81 °F.

What size tank do congo tetras and black neon tetras need together?

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