Can pea puffers live with upside down catfish?

Verdict
Yes, with care

Yes, with care. Pea puffers and upside down catfish can share a tank, but watch one thing. Pea puffers are aggressive, though upside down catfish are big enough to shrug most of it off.

What to watch

What works

Water side by side

55°60°65°70°75°80°85°90°Both: 74–79°Pea puffer 74–82°Upside down catfish 72–79°
The green band is the temperature range both can live in.
456789Both: 7–7.5Pea puffer 7–8Upside down catfish 6–7.5
The green band is the pH both tolerate.

Size to scale

Pea puffer · 1 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

Pea pufferUpside down catfish
Temperature74–82 °F72–79 °F
pH7–86–7.5
Adult size1.0 in4.0 in
Minimum tank5 gal30 gal
TemperamentAggressivePeaceful
Swims atAll levelsBottom
GroupAlone or in pairsGroups of 3+
DietCarnivoreOmnivore

Better tank mates for pea puffers

All pea puffer tank mates

Better tank mates for upside down catfish

All upside down catfish tank mates

Questions

Can pea puffers live with upside down catfish?

Yes, with care. Pea puffers and upside down catfish can share a tank, but watch one thing. Pea puffers are aggressive, though upside down catfish are big enough to shrug most of it off.

What temperature suits both pea puffers and upside down catfish?

74–79 °F. Pea puffers need 74–82 °F, upside down catfish need 72–79 °F.

What size tank do pea puffers and upside down catfish need together?

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