Can otocinclus live with serpae tetras?

Verdict
Yes

Yes, otocinclus and serpae tetras can live together. Both are fine at 72–79°F. Plan on at least 20 gal.

OtocinclusOtocinclus72–79°F · pH 6–7.5 Serpae tetraSerpae tetra72–79°F · pH 6–7.5

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 72–79°Otocinclus 72–79°Serpae tetra 72–79°
The green band is the temperature range both can live in.
456789Both: 6–7.5Otocinclus 6–7.5Serpae tetra 6–7.5
The green band is the pH both tolerate.

Size to scale

Otocinclus · 2 inSerpae tetra · 1.75 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

OtocinclusSerpae tetra
Temperature72–79 °F72–79 °F
pH6–7.56–7.5
Adult size2.0 in1.75 in
Minimum tank20 gal20 gal
TemperamentPeacefulSemi-aggressive
Swims atBottomMiddle
GroupGroups of 6+Groups of 6+
DietHerbivoreOmnivore

Better tank mates for otocinclus

All otocinclus tank mates

Better tank mates for serpae tetras

All serpae tetra tank mates

Questions

Can otocinclus live with serpae tetras?

Yes, otocinclus and serpae tetras can live together. Both are fine at 72–79°F. Plan on at least 20 gal.

What temperature suits both otocinclus and serpae tetras?

72–79 °F. Otocinclus need 72–79 °F, serpae tetras need 72–79 °F.

What size tank do otocinclus and serpae tetras need together?

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