Can harlequin rasboras live with electric blue acaras?

Verdict
Yes

Yes. Harlequin rasboras and electric blue acaras make a good pair. Both are fine at 72–80°F. Plan on at least 30 gal.

Harlequin rasboraHarlequin rasbora72–80°F · pH 6–7.5 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: 72–80°Harlequin rasbora 72–80°Electric blue acara 72–82°
The green band is the temperature range both can live in.
456789Both: 6.5–7.5Harlequin rasbora 6–7.5Electric blue acara 6.5–7.5
The green band is the pH both tolerate.

Size to scale

Harlequin rasbora · 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

Harlequin rasboraElectric blue acara
Temperature72–80 °F72–82 °F
pH6–7.56.5–7.5
Adult size2.0 in6.0 in
Minimum tank10 gal30 gal
TemperamentPeacefulSemi-aggressive
Swims atMiddleMiddle
GroupGroups of 6+Alone or in pairs
DietOmnivoreOmnivore

Better tank mates for harlequin rasboras

All harlequin rasbora tank mates

Better tank mates for electric blue acaras

All electric blue acara tank mates

Questions

Can harlequin rasboras live with electric blue acaras?

Yes. Harlequin rasboras and electric blue acaras make a good pair. Both are fine at 72–80°F. Plan on at least 30 gal.

What temperature suits both harlequin rasboras and electric blue acaras?

72–80 °F. Harlequin rasboras need 72–80 °F, electric blue acaras need 72–82 °F.

What size tank do harlequin rasboras and electric blue acaras need together?

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