Can rummy nose tetras live with pygmy corys?

Verdict
Yes

Yes. Rummy nose tetras and pygmy corys get along in the same tank. Both are fine at 75–79°F. Plan on at least 20 gal.

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 75–79°Rummy nose tetra 75–84°Pygmy cory 72–79°
The green band is the temperature range both can live in.
456789Both: 6–7Rummy nose tetra 5.5–7Pygmy cory 6–7.5
The green band is the pH both tolerate.

Size to scale

Rummy nose tetra · 2 inPygmy cory · 1 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

Rummy nose tetraPygmy cory
Temperature75–84 °F72–79 °F
pH5.5–76–7.5
Adult size2.0 in1.0 in
Minimum tank20 gal10 gal
TemperamentPeacefulPeaceful
Swims atMiddleMiddle
GroupGroups of 6+Groups of 6+
DietOmnivoreOmnivore

Better tank mates for rummy nose tetras

All rummy nose tetra tank mates

Better tank mates for pygmy corys

All pygmy cory tank mates

Questions

Can rummy nose tetras live with pygmy corys?

Yes. Rummy nose tetras and pygmy corys get along in the same tank. Both are fine at 75–79°F. Plan on at least 20 gal.

What temperature suits both rummy nose tetras and pygmy corys?

75–79 °F. Rummy nose tetras need 75–84 °F, pygmy corys need 72–79 °F.

What size tank do rummy nose tetras and pygmy corys need together?

At least 20 gal, set by the rummy nose tetra. Add space for each extra fish.