Can congo tetras live with hatchetfish?

Verdict
Yes

Yes. Congo tetras and hatchetfish make a good pair. Both are fine at 75–81°F. Plan on at least 30 gal.

Congo tetraCongo tetra73–82°F · pH 6–7.5 HatchetfishHatchetfish75–81°F · pH 5.5–7.5

Why it works

Water side by side

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

Size to scale

Congo tetra · 3 inHatchetfish · 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 tetraHatchetfish
Temperature73–82 °F75–81 °F
pH6–7.55.5–7.5
Adult size3.0 in1.5 in
Minimum tank30 gal20 gal
TemperamentPeacefulPeaceful
Swims atMiddleTop
GroupGroups of 6+Groups of 6+
DietOmnivoreCarnivore

Better tank mates for congo tetras

All congo tetra tank mates

Better tank mates for hatchetfish

All hatchetfish tank mates

Questions

Can congo tetras live with hatchetfish?

Yes. Congo tetras and hatchetfish make a good pair. Both are fine at 75–81°F. Plan on at least 30 gal.

What temperature suits both congo tetras and hatchetfish?

75–81 °F. Congo tetras need 73–82 °F, hatchetfish need 75–81 °F.

What size tank do congo tetras and hatchetfish need together?

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