Can fancy goldfish live with rosy barbs?

Verdict
No

No. Fancy goldfish and rosy barbs should not share a tank. Rosy barbs nip fins, and the long fins of fancy goldfish are an easy target.

Fancy goldfishFancy goldfish65–74°F · pH 7–8 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°Both: 65–74°Fancy goldfish 65–74°Rosy barb 64–77°
The green band is the temperature range both can live in.
456789Both: 7–7.5Fancy goldfish 7–8Rosy barb 6–7.5
The green band is the pH both tolerate.

Size to scale

Fancy goldfish · 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

Fancy goldfishRosy barb
Temperature65–74 °F64–77 °F
pH7–86–7.5
Adult size6.0 in4.0 in
Minimum tank30 gal30 gal
TemperamentPeacefulSemi-aggressive
Swims atAll levelsMiddle
GroupAlone or in pairsGroups of 6+
DietOmnivoreOmnivore

Better tank mates for fancy goldfish

All fancy goldfish tank mates

Better tank mates for rosy barbs

All rosy barb tank mates

Questions

Can fancy goldfish live with rosy barbs?

No. Fancy goldfish and rosy barbs should not share a tank. Rosy barbs nip fins, and the long fins of fancy goldfish are an easy target.

What temperature suits both fancy goldfish and rosy barbs?

65–74 °F. Fancy goldfish need 65–74 °F, rosy barbs need 64–77 °F.

What size tank do fancy goldfish and rosy barbs need together?

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