Can discus live with rainbow sharks?

Verdict
No

No. Discus and rainbow sharks should not share a tank. No shared temperature. Discus need 82–88°F, rainbow sharks need 72–80°F.

DiscusDiscus82–88°F · pH 5.5–7 Rainbow sharkRainbow shark72–80°F · pH 6.5–7.5

What to watch

What works

Water side by side

55°60°65°70°75°80°85°90°Discus 82–88°Rainbow shark 72–80°
The ranges do not meet, so one of them would always be too warm or too cold.
456789Both: 6.5–7Discus 5.5–7Rainbow shark 6.5–7.5
The green band is the pH both tolerate.

Size to scale

Discus · 6 inRainbow shark · 6 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

DiscusRainbow shark
Temperature82–88 °F72–80 °F
pH5.5–76.5–7.5
Adult size6.0 in6.0 in
Minimum tank55 gal55 gal
TemperamentPeacefulSemi-aggressive
Swims atMiddleBottom
GroupGroups of 5+One per tank
DietCarnivoreOmnivore

Better tank mates for discus

All discus tank mates

Better tank mates for rainbow sharks

All rainbow shark tank mates

Questions

Can discus live with rainbow sharks?

No. Discus and rainbow sharks should not share a tank. No shared temperature. Discus need 82–88°F, rainbow sharks need 72–80°F.

What temperature suits both discus and rainbow sharks?

None. Discus need 82–88 °F and rainbow sharks need 72–80 °F, so the ranges do not meet.

What size tank do discus and rainbow sharks need together?

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