Can swordtails live with rosy barbs?

Verdict
Yes

Yes, swordtails and rosy barbs can live together. Both are fine at 72–77°F. Plan on at least 30 gal.

SwordtailSwordtail72–79°F · pH 7–8.3 Rosy barbRosy barb64–77°F · pH 6–7.5

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 72–77°Swordtail 72–79°Rosy barb 64–77°
The green band is the temperature range both can live in.
456789Both: 7–7.5Swordtail 7–8.3Rosy barb 6–7.5
The green band is the pH both tolerate.

Size to scale

Swordtail · 5 inRosy barb · 4 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

SwordtailRosy barb
Temperature72–79 °F64–77 °F
pH7–8.36–7.5
Adult size5.0 in4.0 in
Minimum tank30 gal30 gal
TemperamentSemi-aggressiveSemi-aggressive
Swims atMiddleMiddle
GroupGroups of 3+Groups of 6+
DietOmnivoreOmnivore

Better tank mates for swordtails

All swordtail tank mates

Better tank mates for rosy barbs

All rosy barb tank mates

Questions

Can swordtails live with rosy barbs?

Yes, swordtails and rosy barbs can live together. Both are fine at 72–77°F. Plan on at least 30 gal.

What temperature suits both swordtails and rosy barbs?

72–77 °F. Swordtails need 72–79 °F, rosy barbs need 64–77 °F.

What size tank do swordtails and rosy barbs need together?

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