Can upside down catfish live with zebra loaches?

Verdict
Yes

Yes. Upside down catfish and zebra loaches make a good pair. Both are fine at 73–79°F. Plan on at least 30 gal.

Upside down catfishUpside down catfish72–79°F · pH 6–7.5 Zebra loachZebra loach73–79°F · pH 6–7.5

Why it works

Water side by side

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

Size to scale

Upside down catfish · 4 inZebra loach · 3.5 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 catfishZebra loach
Temperature72–79 °F73–79 °F
pH6–7.56–7.5
Adult size4.0 in3.5 in
Minimum tank30 gal30 gal
TemperamentPeacefulPeaceful
Swims atBottomBottom
GroupGroups of 3+Groups of 5+
DietOmnivoreOmnivore

Better tank mates for upside down catfish

All upside down catfish tank mates

Better tank mates for zebra loaches

All zebra loach tank mates

Questions

Can upside down catfish live with zebra loaches?

Yes. Upside down catfish and zebra loaches make a good pair. Both are fine at 73–79°F. Plan on at least 30 gal.

What temperature suits both upside down catfish and zebra loaches?

73–79 °F. Upside down catfish need 72–79 °F, zebra loaches need 73–79 °F.

What size tank do upside down catfish and zebra loaches need together?

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