Can pea puffers live with pencilfish?

Verdict

Yes, with care

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

Pea puffer74–82°F · pH 7–8

Pencilfish75–82°F · pH 5–7.5

What to watch

Watch outPea puffers are aggressive, though pencilfish are big enough to shrug most of it off.

What works

Both are fine at 75–82°F.
pH 7–7.5 suits both.

Water side by side

The green band is the temperature range both can live in.

The green band is the pH both tolerate.

Size to scale

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 puffer	Pencilfish
Temperature	74–82 °F	75–82 °F
pH	7–8	5–7.5
Adult size	1.0 in	2.0 in
Minimum tank	5 gal	15 gal
Temperament	Aggressive	Peaceful
Swims at	All levels	Middle
Group	Alone or in pairs	Groups of 6+
Diet	Carnivore	Omnivore

Better tank mates for pea puffers

CrayfishYes

All pea puffer tank mates

Better tank mates for pencilfish

All pencilfish tank mates

Questions

Can pea puffers live with pencilfish?

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

What temperature suits both pea puffers and pencilfish?

75–82 °F. Pea puffers need 74–82 °F, pencilfish need 75–82 °F.

What size tank do pea puffers and pencilfish need together?

At least 15 gal, set by the pencilfish. Add space for each extra fish.