Can pencilfish live with glofish?

Verdict
Yes

Yes, pencilfish and glofish can live together. Both are fine at 75–80°F. Plan on at least 15 gal.

PencilfishPencilfish75–82°F · pH 5–7.5 GloFish tetraGloFish tetra72–80°F · pH 6–7.5

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 75–80°Pencilfish 75–82°GloFish tetra 72–80°
The green band is the temperature range both can live in.
456789Both: 6–7.5Pencilfish 5–7.5GloFish tetra 6–7.5
The green band is the pH both tolerate.

Size to scale

Pencilfish · 2 inGloFish tetra · 2.5 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

PencilfishGloFish tetra
Temperature75–82 °F72–80 °F
pH5–7.56–7.5
Adult size2.0 in2.5 in
Minimum tank15 gal15 gal
TemperamentPeacefulSemi-aggressive
Swims atMiddleMiddle
GroupGroups of 6+Groups of 6+
DietOmnivoreOmnivore

Better tank mates for pencilfish

All pencilfish tank mates

Better tank mates for glofish

All glofish tetra tank mates

Questions

Can pencilfish live with glofish?

Yes, pencilfish and glofish can live together. Both are fine at 75–80°F. Plan on at least 15 gal.

What temperature suits both pencilfish and glofish?

75–80 °F. Pencilfish need 75–82 °F, glofish need 72–80 °F.

What size tank do pencilfish and glofish need together?

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