Can otocinclus live with glass catfish?

Verdict
Yes

Yes. Otocinclus and glass catfish make a good pair. Both are fine at 75–79°F. Plan on at least 30 gal.

OtocinclusOtocinclus72–79°F · pH 6–7.5 Glass catfishGlass catfish75–80°F · pH 6.5–7.5

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 75–79°Otocinclus 72–79°Glass catfish 75–80°
The green band is the temperature range both can live in.
456789Both: 6.5–7.5Otocinclus 6–7.5Glass catfish 6.5–7.5
The green band is the pH both tolerate.

Size to scale

Otocinclus · 2 inGlass catfish · 3 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

OtocinclusGlass catfish
Temperature72–79 °F75–80 °F
pH6–7.56.5–7.5
Adult size2.0 in3.0 in
Minimum tank20 gal30 gal
TemperamentPeacefulPeaceful
Swims atBottomMiddle
GroupGroups of 6+Groups of 6+
DietHerbivoreCarnivore

Better tank mates for otocinclus

All otocinclus tank mates

Better tank mates for glass catfish

All glass catfish tank mates

Questions

Can otocinclus live with glass catfish?

Yes. Otocinclus and glass catfish make a good pair. Both are fine at 75–79°F. Plan on at least 30 gal.

What temperature suits both otocinclus and glass catfish?

75–79 °F. Otocinclus need 72–79 °F, glass catfish need 75–80 °F.

What size tank do otocinclus and glass catfish need together?

At least 30 gal, set by the glass catfish. Add space for each extra fish.