Can rummy nose tetras live with electric blue acaras?

Verdict
Yes

Yes. Rummy nose tetras and electric blue acaras get along in the same tank. Both are fine at 75–82°F. Plan on at least 30 gal.

Rummy nose tetraRummy nose tetra75–84°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: 75–82°Rummy nose tetra 75–84°Electric blue acara 72–82°
The green band is the temperature range both can live in.
456789Both: 6.5–7Rummy nose tetra 5.5–7Electric blue acara 6.5–7.5
The green band is the pH both tolerate.

Size to scale

Rummy nose tetra · 2 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

Rummy nose tetraElectric blue acara
Temperature75–84 °F72–82 °F
pH5.5–76.5–7.5
Adult size2.0 in6.0 in
Minimum tank20 gal30 gal
TemperamentPeacefulSemi-aggressive
Swims atMiddleMiddle
GroupGroups of 6+Alone or in pairs
DietOmnivoreOmnivore

Better tank mates for rummy nose tetras

All rummy nose tetra tank mates

Better tank mates for electric blue acaras

All electric blue acara tank mates

Questions

Can rummy nose tetras live with electric blue acaras?

Yes. Rummy nose tetras and electric blue acaras get along in the same tank. Both are fine at 75–82°F. Plan on at least 30 gal.

What temperature suits both rummy nose tetras and electric blue acaras?

75–82 °F. Rummy nose tetras need 75–84 °F, electric blue acaras need 72–82 °F.

What size tank do rummy nose tetras and electric blue acaras need together?

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