Can neon tetras live with upside down catfish?

Verdict
Yes

Yes, neon tetras and upside down catfish can live together. Both are fine at 72–79°F. Plan on at least 30 gal.

Neon tetraNeon tetra72–79°F · pH 6–7 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°Neon tetra 72–79°Upside down catfish 72–79°
The green band is the temperature range both can live in.
456789Both: 6–7Neon tetra 6–7Upside down catfish 6–7.5
The green band is the pH both tolerate.

Size to scale

Neon tetra · 1.5 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

Neon tetraUpside down catfish
Temperature72–79 °F72–79 °F
pH6–76–7.5
Adult size1.5 in4.0 in
Minimum tank10 gal30 gal
TemperamentPeacefulPeaceful
Swims atMiddleBottom
GroupGroups of 6+Groups of 3+
DietOmnivoreOmnivore

Better tank mates for neon tetras

All neon tetra tank mates

Better tank mates for upside down catfish

All upside down catfish tank mates

Questions

Can neon tetras live with upside down catfish?

Yes, neon tetras and upside down catfish can live together. Both are fine at 72–79°F. Plan on at least 30 gal.

What temperature suits both neon tetras and upside down catfish?

72–79 °F. Neon tetras need 72–79 °F, upside down catfish need 72–79 °F.

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

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