Can killifish live with gold barbs?

Verdict
Yes

Yes, killifish and gold barbs can live together. Both are fine at 70–75°F. Plan on at least 20 gal.

KillifishKillifish70–77°F · pH 5.5–7 Gold barbGold barb64–75°F · pH 6–8

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 70–75°Killifish 70–77°Gold barb 64–75°
The green band is the temperature range both can live in.
456789Both: 6–7Killifish 5.5–7Gold barb 6–8
The green band is the pH both tolerate.

Size to scale

Killifish · 2.5 inGold barb · 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

KillifishGold barb
Temperature70–77 °F64–75 °F
pH5.5–76–8
Adult size2.5 in3.0 in
Minimum tank10 gal20 gal
TemperamentPeacefulPeaceful
Swims atTopMiddle
GroupAlone or in pairsGroups of 6+
DietCarnivoreOmnivore

Better tank mates for killifish

All killifish tank mates

Better tank mates for gold barbs

All gold barb tank mates

Questions

Can killifish live with gold barbs?

Yes, killifish and gold barbs can live together. Both are fine at 70–75°F. Plan on at least 20 gal.

What temperature suits both killifish and gold barbs?

70–75 °F. Killifish need 70–77 °F, gold barbs need 64–75 °F.

What size tank do killifish and gold barbs need together?

At least 20 gal, set by the gold barb. Add space for each extra fish.