Can harlequin rasboras live with blue gouramis?

Verdict
Yes

Yes. Harlequin rasboras and blue gouramis 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 Blue gouramiBlue gourami72–82°F · pH 6–8

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 72–80°Harlequin rasbora 72–80°Blue gourami 72–82°
The green band is the temperature range both can live in.
456789Both: 6–7.5Harlequin rasbora 6–7.5Blue gourami 6–8
The green band is the pH both tolerate.

Size to scale

Harlequin rasbora · 2 inBlue gourami · 5 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 rasboraBlue gourami
Temperature72–80 °F72–82 °F
pH6–7.56–8
Adult size2.0 in5.0 in
Minimum tank10 gal30 gal
TemperamentPeacefulSemi-aggressive
Swims atMiddleTop
GroupGroups of 6+Alone or in pairs
DietOmnivoreOmnivore

Better tank mates for harlequin rasboras

All harlequin rasbora tank mates

Better tank mates for blue gouramis

All blue gourami tank mates

Questions

Can harlequin rasboras live with blue gouramis?

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

What temperature suits both harlequin rasboras and blue gouramis?

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

What size tank do harlequin rasboras and blue gouramis need together?

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