Can discus live with rosy barbs?

Verdict
No

No. Discus and rosy barbs should not share a tank. No shared temperature. Discus need 82–88°F, rosy barbs need 64–77°F.

DiscusDiscus82–88°F · pH 5.5–7 Rosy barbRosy barb64–77°F · pH 6–7.5

What to watch

What works

Water side by side

55°60°65°70°75°80°85°90°Discus 82–88°Rosy barb 64–77°
The ranges do not meet, so one of them would always be too warm or too cold.
456789Both: 6–7Discus 5.5–7Rosy barb 6–7.5
The green band is the pH both tolerate.

Size to scale

Discus · 6 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

DiscusRosy barb
Temperature82–88 °F64–77 °F
pH5.5–76–7.5
Adult size6.0 in4.0 in
Minimum tank55 gal30 gal
TemperamentPeacefulSemi-aggressive
Swims atMiddleMiddle
GroupGroups of 5+Groups of 6+
DietCarnivoreOmnivore

Better tank mates for discus

All discus tank mates

Better tank mates for rosy barbs

All rosy barb tank mates

Questions

Can discus live with rosy barbs?

No. Discus and rosy barbs should not share a tank. No shared temperature. Discus need 82–88°F, rosy barbs need 64–77°F.

What temperature suits both discus and rosy barbs?

None. Discus need 82–88 °F and rosy barbs need 64–77 °F, so the ranges do not meet.

What size tank do discus and rosy barbs need together?

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