Can fancy goldfish live with electric blue acaras?

Verdict
No

No. Fancy goldfish and electric blue acaras should not share a tank. Fancy goldfish are coldwater animals (65–74°F); electric blue acaras need 72–82°F. They overlap only at 72–74°F, the edge of both ranges.

Fancy goldfishFancy goldfish65–74°F · pH 7–8 Electric blue acaraElectric blue acara72–82°F · pH 6.5–7.5

What to watch

What works

Water side by side

55°60°65°70°75°80°85°90°Both: 72–74°Fancy goldfish 65–74°Electric blue acara 72–82°
The green band is the temperature range both can live in.
456789Both: 7–7.5Fancy goldfish 7–8Electric blue acara 6.5–7.5
The green band is the pH both tolerate.

Size to scale

Fancy goldfish · 6 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

Fancy goldfishElectric blue acara
Temperature65–74 °F72–82 °F
pH7–86.5–7.5
Adult size6.0 in6.0 in
Minimum tank30 gal30 gal
TemperamentPeacefulSemi-aggressive
Swims atAll levelsMiddle
GroupAlone or in pairsAlone or in pairs
DietOmnivoreOmnivore

Better tank mates for fancy goldfish

All fancy goldfish tank mates

Better tank mates for electric blue acaras

All electric blue acara tank mates

Questions

Can fancy goldfish live with electric blue acaras?

No. Fancy goldfish and electric blue acaras should not share a tank. Fancy goldfish are coldwater animals (65–74°F); electric blue acaras need 72–82°F. They overlap only at 72–74°F, the edge of both ranges.

What temperature suits both fancy goldfish and electric blue acaras?

72–74 °F. Fancy goldfish need 65–74 °F, electric blue acaras need 72–82 °F.

What size tank do fancy goldfish and electric blue acaras need together?

At least 30 gal, set by the fancy goldfish. Add space for each extra fish.