Can bristlenose plecos live with rosy barbs?

Verdict
Yes

Yes. Bristlenose plecos and rosy barbs make a good pair. Both are fine at 73–77°F. Plan on at least 30 gal.

Bristlenose plecoBristlenose pleco73–81°F · pH 6.5–7.5 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: 73–77°Bristlenose pleco 73–81°Rosy barb 64–77°
The green band is the temperature range both can live in.
456789Both: 6.5–7.5Bristlenose pleco 6.5–7.5Rosy barb 6–7.5
The green band is the pH both tolerate.

Size to scale

Bristlenose pleco · 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

Bristlenose plecoRosy barb
Temperature73–81 °F64–77 °F
pH6.5–7.56–7.5
Adult size5.0 in4.0 in
Minimum tank30 gal30 gal
TemperamentPeacefulSemi-aggressive
Swims atBottomMiddle
GroupAlone or in pairsGroups of 6+
DietHerbivoreOmnivore

Better tank mates for bristlenose plecos

All bristlenose pleco tank mates

Better tank mates for rosy barbs

All rosy barb tank mates

Questions

Can bristlenose plecos live with rosy barbs?

Yes. Bristlenose plecos and rosy barbs make a good pair. Both are fine at 73–77°F. Plan on at least 30 gal.

What temperature suits both bristlenose plecos and rosy barbs?

73–77 °F. Bristlenose plecos need 73–81 °F, rosy barbs need 64–77 °F.

What size tank do bristlenose plecos and rosy barbs need together?

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