Can black skirt tetras live with upside down catfish?

Verdict
Yes

Yes. Black skirt tetras and upside down catfish make a good pair. Both are fine at 72–79°F. Plan on at least 30 gal.

Black skirt tetraBlack skirt tetra70–80°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°Black skirt tetra 70–80°Upside down catfish 72–79°
The green band is the temperature range both can live in.
456789Both: 6–7.5Black skirt tetra 6–7.5Upside down catfish 6–7.5
The green band is the pH both tolerate.

Size to scale

Black skirt tetra · 2.5 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

Black skirt tetraUpside down catfish
Temperature70–80 °F72–79 °F
pH6–7.56–7.5
Adult size2.5 in4.0 in
Minimum tank15 gal30 gal
TemperamentSemi-aggressivePeaceful
Swims atMiddleBottom
GroupGroups of 6+Groups of 3+
DietOmnivoreOmnivore

Better tank mates for black skirt tetras

All black skirt tetra tank mates

Better tank mates for upside down catfish

All upside down catfish tank mates

Questions

Can black skirt tetras live with upside down catfish?

Yes. Black skirt tetras and upside down catfish make a good pair. Both are fine at 72–79°F. Plan on at least 30 gal.

What temperature suits both black skirt tetras and upside down catfish?

72–79 °F. Black skirt tetras need 70–80 °F, upside down catfish need 72–79 °F.

What size tank do black skirt tetras and upside down catfish need together?

At least 30 gal, set by the upside down catfish. Add space for each extra fish.