Can discus live with otocinclus?

Verdict
No

No. Discus and otocinclus should not share a tank. No shared temperature. Discus need 82–88°F, otocinclus need 72–79°F.

DiscusDiscus82–88°F · pH 5.5–7 OtocinclusOtocinclus72–79°F · pH 6–7.5

What to watch

What works

Water side by side

55°60°65°70°75°80°85°90°Discus 82–88°Otocinclus 72–79°
The ranges do not meet, so one of them would always be too warm or too cold.
456789Both: 6–7Discus 5.5–7Otocinclus 6–7.5
The green band is the pH both tolerate.

Size to scale

Discus · 6 inOtocinclus · 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

DiscusOtocinclus
Temperature82–88 °F72–79 °F
pH5.5–76–7.5
Adult size6.0 in2.0 in
Minimum tank55 gal20 gal
TemperamentPeacefulPeaceful
Swims atMiddleBottom
GroupGroups of 5+Groups of 6+
DietCarnivoreHerbivore

Better tank mates for discus

All discus tank mates

Better tank mates for otocinclus

All otocinclus tank mates

Questions

Can discus live with otocinclus?

No. Discus and otocinclus should not share a tank. No shared temperature. Discus need 82–88°F, otocinclus need 72–79°F.

What temperature suits both discus and otocinclus?

None. Discus need 82–88 °F and otocinclus need 72–79 °F, so the ranges do not meet.

What size tank do discus and otocinclus need together?

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