Can hillstream loaches live with black neon tetras?

Verdict
Yes

Yes. Hillstream loaches and black neon tetras make a good pair. Both are fine at 73–75°F. Plan on at least 20 gal.

Hillstream loachHillstream loach68–75°F · pH 6.5–7.5 Black neon tetraBlack neon tetra73–81°F · pH 5.5–7.5

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 73–75°Hillstream loach 68–75°Black neon tetra 73–81°
The green band is the temperature range both can live in.
456789Both: 6.5–7.5Hillstream loach 6.5–7.5Black neon tetra 5.5–7.5
The green band is the pH both tolerate.

Size to scale

Hillstream loach · 2.5 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

Hillstream loachBlack neon tetra
Temperature68–75 °F73–81 °F
pH6.5–7.55.5–7.5
Adult size2.5 in1.5 in
Minimum tank20 gal15 gal
TemperamentPeacefulPeaceful
Swims atBottomMiddle
GroupGroups of 3+Groups of 6+
DietHerbivoreOmnivore

Better tank mates for hillstream loaches

All hillstream loach tank mates

Better tank mates for black neon tetras

All black neon tetra tank mates

Questions

Can hillstream loaches live with black neon tetras?

Yes. Hillstream loaches and black neon tetras make a good pair. Both are fine at 73–75°F. Plan on at least 20 gal.

What temperature suits both hillstream loaches and black neon tetras?

73–75 °F. Hillstream loaches need 68–75 °F, black neon tetras need 73–81 °F.

What size tank do hillstream loaches and black neon tetras need together?

At least 20 gal, set by the hillstream loach. Add space for each extra fish.