Can tiger barbs live with upside down catfish?

Verdict
Yes

Yes. Tiger barbs and upside down catfish get along in the same tank. Both are fine at 72–79°F. Plan on at least 30 gal.

Tiger barbTiger barb72–81°F · pH 6–7.5 Upside down catfishUpside down catfish72–79°F · pH 6–7.5

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 72–79°Tiger barb 72–81°Upside down catfish 72–79°
The green band is the temperature range both can live in.
456789Both: 6–7.5Tiger barb 6–7.5Upside down catfish 6–7.5
The green band is the pH both tolerate.

Size to scale

Tiger barb · 3 inUpside down catfish · 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

Tiger barbUpside down catfish
Temperature72–81 °F72–79 °F
pH6–7.56–7.5
Adult size3.0 in4.0 in
Minimum tank30 gal30 gal
TemperamentSemi-aggressivePeaceful
Swims atMiddleBottom
GroupGroups of 6+Groups of 3+
DietOmnivoreOmnivore

Better tank mates for tiger barbs

All tiger barb tank mates

Better tank mates for upside down catfish

All upside down catfish tank mates

Questions

Can tiger barbs live with upside down catfish?

Yes. Tiger barbs and upside down catfish get along in the same tank. Both are fine at 72–79°F. Plan on at least 30 gal.

What temperature suits both tiger barbs and upside down catfish?

72–79 °F. Tiger barbs need 72–81 °F, upside down catfish need 72–79 °F.

What size tank do tiger barbs and upside down catfish need together?

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