Can killifish live with glowlight tetras?

Verdict
Yes

Yes. Killifish and glowlight tetras get along in the same tank. Both are fine at 74–77°F. Plan on at least 10 gal.

KillifishKillifish70–77°F · pH 5.5–7 Glowlight tetraGlowlight tetra74–80°F · pH 6–7.5

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 74–77°Killifish 70–77°Glowlight tetra 74–80°
The green band is the temperature range both can live in.
456789Both: 6–7Killifish 5.5–7Glowlight tetra 6–7.5
The green band is the pH both tolerate.

Size to scale

Killifish · 2.5 inGlowlight 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

KillifishGlowlight tetra
Temperature70–77 °F74–80 °F
pH5.5–76–7.5
Adult size2.5 in1.5 in
Minimum tank10 gal10 gal
TemperamentPeacefulPeaceful
Swims atTopMiddle
GroupAlone or in pairsGroups of 6+
DietCarnivoreOmnivore

Better tank mates for killifish

All killifish tank mates

Better tank mates for glowlight tetras

All glowlight tetra tank mates

Questions

Can killifish live with glowlight tetras?

Yes. Killifish and glowlight tetras get along in the same tank. Both are fine at 74–77°F. Plan on at least 10 gal.

What temperature suits both killifish and glowlight tetras?

74–77 °F. Killifish need 70–77 °F, glowlight tetras need 74–80 °F.

What size tank do killifish and glowlight tetras need together?

At least 10 gal, set by the killifish. Add space for each extra fish.