Can rainbow sharks live with rummy nose tetras?

Verdict
Yes

Yes. Rainbow sharks and rummy nose tetras make a good pair. Both are fine at 75–80°F. Plan on at least 55 gal.

Rainbow sharkRainbow shark72–80°F · pH 6.5–7.5 Rummy nose tetraRummy nose tetra75–84°F · pH 5.5–7

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 75–80°Rainbow shark 72–80°Rummy nose tetra 75–84°
The green band is the temperature range both can live in.
456789Both: 6.5–7Rainbow shark 6.5–7.5Rummy nose tetra 5.5–7
The green band is the pH both tolerate.

Size to scale

Rainbow shark · 6 inRummy nose tetra · 2 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 sharkRummy nose tetra
Temperature72–80 °F75–84 °F
pH6.5–7.55.5–7
Adult size6.0 in2.0 in
Minimum tank55 gal20 gal
TemperamentSemi-aggressivePeaceful
Swims atBottomMiddle
GroupOne per tankGroups of 6+
DietOmnivoreOmnivore

Better tank mates for rainbow sharks

All rainbow shark tank mates

Better tank mates for rummy nose tetras

All rummy nose tetra tank mates

Questions

Can rainbow sharks live with rummy nose tetras?

Yes. Rainbow sharks and rummy nose tetras make a good pair. Both are fine at 75–80°F. Plan on at least 55 gal.

What temperature suits both rainbow sharks and rummy nose tetras?

75–80 °F. Rainbow sharks need 72–80 °F, rummy nose tetras need 75–84 °F.

What size tank do rainbow sharks and rummy nose tetras need together?

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