Can killifish live with electric blue acaras?

Verdict
Yes

Yes, killifish and electric blue acaras can live together. Both are fine at 72–77°F. Plan on at least 30 gal.

KillifishKillifish70–77°F · pH 5.5–7 Electric blue acaraElectric blue acara72–82°F · pH 6.5–7.5

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 72–77°Killifish 70–77°Electric blue acara 72–82°
The green band is the temperature range both can live in.
456789Both: 6.5–7Killifish 5.5–7Electric blue acara 6.5–7.5
The green band is the pH both tolerate.

Size to scale

Killifish · 2.5 inElectric blue acara · 6 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

KillifishElectric blue acara
Temperature70–77 °F72–82 °F
pH5.5–76.5–7.5
Adult size2.5 in6.0 in
Minimum tank10 gal30 gal
TemperamentPeacefulSemi-aggressive
Swims atTopMiddle
GroupAlone or in pairsAlone or in pairs
DietCarnivoreOmnivore

Better tank mates for killifish

All killifish tank mates

Better tank mates for electric blue acaras

All electric blue acara tank mates

Questions

Can killifish live with electric blue acaras?

Yes, killifish and electric blue acaras can live together. Both are fine at 72–77°F. Plan on at least 30 gal.

What temperature suits both killifish and electric blue acaras?

72–77 °F. Killifish need 70–77 °F, electric blue acaras need 72–82 °F.

What size tank do killifish and electric blue acaras need together?

At least 30 gal, set by the electric blue acara. Add space for each extra fish.