Can discus live with black neon tetras?

Verdict
No

No. Discus and black neon tetras should not share a tank. No shared temperature. Discus need 82–88°F, black neon tetras need 73–81°F.

DiscusDiscus82–88°F · pH 5.5–7 Black neon tetraBlack neon tetra73–81°F · pH 5.5–7.5

What to watch

What works

Water side by side

55°60°65°70°75°80°85°90°Discus 82–88°Black neon tetra 73–81°
The ranges do not meet, so one of them would always be too warm or too cold.
456789Both: 5.5–7Discus 5.5–7Black neon tetra 5.5–7.5
The green band is the pH both tolerate.

Size to scale

Discus · 6 inBlack neon tetra · 1.5 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

DiscusBlack neon tetra
Temperature82–88 °F73–81 °F
pH5.5–75.5–7.5
Adult size6.0 in1.5 in
Minimum tank55 gal15 gal
TemperamentPeacefulPeaceful
Swims atMiddleMiddle
GroupGroups of 5+Groups of 6+
DietCarnivoreOmnivore

Better tank mates for discus

All discus tank mates

Better tank mates for black neon tetras

All black neon tetra tank mates

Questions

Can discus live with black neon tetras?

No. Discus and black neon tetras should not share a tank. No shared temperature. Discus need 82–88°F, black neon tetras need 73–81°F.

What temperature suits both discus and black neon tetras?

None. Discus need 82–88 °F and black neon tetras need 73–81 °F, so the ranges do not meet.

What size tank do discus and black neon tetras need together?

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