Can rosy barbs live with lemon tetras?

Verdict
Yes

Yes. Rosy barbs and lemon tetras get along in the same tank. Both are fine at 72–77°F. Plan on at least 30 gal.

Rosy barbRosy barb64–77°F · pH 6–7.5 Lemon tetraLemon tetra72–82°F · pH 5.5–7.5

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 72–77°Rosy barb 64–77°Lemon tetra 72–82°
The green band is the temperature range both can live in.
456789Both: 6–7.5Rosy barb 6–7.5Lemon tetra 5.5–7.5
The green band is the pH both tolerate.

Size to scale

Rosy barb · 4 inLemon tetra · 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

Rosy barbLemon tetra
Temperature64–77 °F72–82 °F
pH6–7.55.5–7.5
Adult size4.0 in2.0 in
Minimum tank30 gal15 gal
TemperamentSemi-aggressivePeaceful
Swims atMiddleMiddle
GroupGroups of 6+Groups of 6+
DietOmnivoreOmnivore

Better tank mates for rosy barbs

All rosy barb tank mates

Better tank mates for lemon tetras

All lemon tetra tank mates

Questions

Can rosy barbs live with lemon tetras?

Yes. Rosy barbs and lemon tetras get along in the same tank. Both are fine at 72–77°F. Plan on at least 30 gal.

What temperature suits both rosy barbs and lemon tetras?

72–77 °F. Rosy barbs need 64–77 °F, lemon tetras need 72–82 °F.

What size tank do rosy barbs and lemon tetras need together?

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