Can rainbow sharks live with serpae tetras?

Verdict
Yes

Yes. Rainbow sharks and serpae tetras get along in the same tank. Both are fine at 72–79°F. Plan on at least 55 gal.

Rainbow sharkRainbow shark72–80°F · pH 6.5–7.5 Serpae tetraSerpae tetra72–79°F · pH 6–7.5

Why it works

Water side by side

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

Size to scale

Rainbow shark · 6 inSerpae tetra · 1.75 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

Rainbow sharkSerpae tetra
Temperature72–80 °F72–79 °F
pH6.5–7.56–7.5
Adult size6.0 in1.75 in
Minimum tank55 gal20 gal
TemperamentSemi-aggressiveSemi-aggressive
Swims atBottomMiddle
GroupOne per tankGroups of 6+
DietOmnivoreOmnivore

Better tank mates for rainbow sharks

All rainbow shark tank mates

Better tank mates for serpae tetras

All serpae tetra tank mates

Questions

Can rainbow sharks live with serpae tetras?

Yes. Rainbow sharks and serpae tetras get along in the same tank. Both are fine at 72–79°F. Plan on at least 55 gal.

What temperature suits both rainbow sharks and serpae tetras?

72–79 °F. Rainbow sharks need 72–80 °F, serpae tetras need 72–79 °F.

What size tank do rainbow sharks and serpae tetras need together?

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