Living in alkalescent, warm (24–28°), and slow-flowing rivers, Pao palembangensis is a distinct fish.

It grows to a length of 19.4 centimetres (7.6 in) SL, with both sexes having a similar body size, but the male having a much larger rear hump.

[citation needed] As a pufferfish its body contains the neurotoxin tetrodotoxin (TTX),[6] and it can swell up to three times its normal size as a defence mechanism when threatened.

[citation needed] P. palembangensis is an active hunter that pursues sleeping aquatic prey.

It is a nocturnal fish as evidence by its large eyes, increased nightly activity, and daytime sleep.