Can tiger barbs live with rainbow sharks?

Verdict
Yes

Yes. Tiger barbs and rainbow sharks get along in the same tank. Both are fine at 72–80°F. Plan on at least 55 gal.

Tiger barbTiger barb72–81°F · pH 6–7.5 Rainbow sharkRainbow shark72–80°F · pH 6.5–7.5

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 72–80°Tiger barb 72–81°Rainbow shark 72–80°
The green band is the temperature range both can live in.
456789Both: 6.5–7.5Tiger barb 6–7.5Rainbow shark 6.5–7.5
The green band is the pH both tolerate.

Size to scale

Tiger barb · 3 inRainbow shark · 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

Tiger barbRainbow shark
Temperature72–81 °F72–80 °F
pH6–7.56.5–7.5
Adult size3.0 in6.0 in
Minimum tank30 gal55 gal
TemperamentSemi-aggressiveSemi-aggressive
Swims atMiddleBottom
GroupGroups of 6+One per tank
DietOmnivoreOmnivore

Better tank mates for tiger barbs

All tiger barb tank mates

Better tank mates for rainbow sharks

All rainbow shark tank mates

Questions

Can tiger barbs live with rainbow sharks?

Yes. Tiger barbs and rainbow sharks get along in the same tank. Both are fine at 72–80°F. Plan on at least 55 gal.

What temperature suits both tiger barbs and rainbow sharks?

72–80 °F. Tiger barbs need 72–81 °F, rainbow sharks need 72–80 °F.

What size tank do tiger barbs and rainbow sharks need together?

At least 55 gal, set by the rainbow shark. Add space for each extra fish.