Can neon tetras live with red tail sharks?

Verdict
Yes

Yes. Neon tetras and red tail sharks make a good pair. Both are fine at 72–79°F. Plan on at least 55 gal.

Neon tetraNeon tetra72–79°F · pH 6–7 Red tail sharkRed tail shark72–79°F · pH 6.5–7.5

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 72–79°Neon tetra 72–79°Red tail shark 72–79°
The green band is the temperature range both can live in.
456789Both: 6.5–7Neon tetra 6–7Red tail shark 6.5–7.5
The green band is the pH both tolerate.

Size to scale

Neon tetra · 1.5 inRed tail shark · 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

Neon tetraRed tail shark
Temperature72–79 °F72–79 °F
pH6–76.5–7.5
Adult size1.5 in5.0 in
Minimum tank10 gal55 gal
TemperamentPeacefulSemi-aggressive
Swims atMiddleBottom
GroupGroups of 6+One per tank
DietOmnivoreOmnivore

Better tank mates for neon tetras

All neon tetra tank mates

Better tank mates for red tail sharks

All red tail shark tank mates

Questions

Can neon tetras live with red tail sharks?

Yes. Neon tetras and red tail sharks make a good pair. Both are fine at 72–79°F. Plan on at least 55 gal.

What temperature suits both neon tetras and red tail sharks?

72–79 °F. Neon tetras need 72–79 °F, red tail sharks need 72–79 °F.

What size tank do neon tetras and red tail sharks need together?

At least 55 gal, set by the red tail shark. Add space for each extra fish.