Can upside down catfish live with black neon tetras?

Verdict
Yes

Yes, upside down catfish and black neon tetras can live together. Both are fine at 73–79°F. Plan on at least 30 gal.

Upside down catfishUpside down catfish72–79°F · pH 6–7.5 Black neon tetraBlack neon tetra73–81°F · pH 5.5–7.5

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 73–79°Upside down catfish 72–79°Black neon tetra 73–81°
The green band is the temperature range both can live in.
456789Both: 6–7.5Upside down catfish 6–7.5Black neon tetra 5.5–7.5
The green band is the pH both tolerate.

Size to scale

Upside down catfish · 4 inBlack neon tetra · 1.5 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

Upside down catfishBlack neon tetra
Temperature72–79 °F73–81 °F
pH6–7.55.5–7.5
Adult size4.0 in1.5 in
Minimum tank30 gal15 gal
TemperamentPeacefulPeaceful
Swims atBottomMiddle
GroupGroups of 3+Groups of 6+
DietOmnivoreOmnivore

Better tank mates for upside down catfish

All upside down catfish tank mates

Better tank mates for black neon tetras

All black neon tetra tank mates

Questions

Can upside down catfish live with black neon tetras?

Yes, upside down catfish and black neon tetras can live together. Both are fine at 73–79°F. Plan on at least 30 gal.

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

73–79 °F. Upside down catfish need 72–79 °F, black neon tetras need 73–81 °F.

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

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