Can tiger barbs live with harlequin rasboras?

Verdict
Yes

Yes, tiger barbs and harlequin rasboras can live together. Both are fine at 72–80°F. Plan on at least 30 gal.

Tiger barbTiger barb72–81°F · pH 6–7.5 Harlequin rasboraHarlequin rasbora72–80°F · pH 6–7.5

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 72–80°Tiger barb 72–81°Harlequin rasbora 72–80°
The green band is the temperature range both can live in.
456789Both: 6–7.5Tiger barb 6–7.5Harlequin rasbora 6–7.5
The green band is the pH both tolerate.

Size to scale

Tiger barb · 3 inHarlequin rasbora · 2 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

Tiger barbHarlequin rasbora
Temperature72–81 °F72–80 °F
pH6–7.56–7.5
Adult size3.0 in2.0 in
Minimum tank30 gal10 gal
TemperamentSemi-aggressivePeaceful
Swims atMiddleMiddle
GroupGroups of 6+Groups of 6+
DietOmnivoreOmnivore

Better tank mates for tiger barbs

All tiger barb tank mates

Better tank mates for harlequin rasboras

All harlequin rasbora tank mates

Questions

Can tiger barbs live with harlequin rasboras?

Yes, tiger barbs and harlequin rasboras can live together. Both are fine at 72–80°F. Plan on at least 30 gal.

What temperature suits both tiger barbs and harlequin rasboras?

72–80 °F. Tiger barbs need 72–81 °F, harlequin rasboras need 72–80 °F.

What size tank do tiger barbs and harlequin rasboras need together?

At least 30 gal, set by the tiger barb. Add space for each extra fish.