It is found in forest streams northwest of Pebas town in northern Peru.

This species is a facultative, biparental larvophilous mouthbrooder, which is unusual in the genus Apistogramma.

This species may also keep the eggs and young fry in a shallow pit throughout the brood care process, thus bypassing a mouthbrooding phase.

[3] Apistogramma barlowi prefers relatively cool and clear fast-flowing forest streams with an acidic to neutral pH.

[2] In one case, the habitat was a 1 m (3.3 ft) wide stream with a sandy bottom (no aquatic plants or large stones), a pH of 4.8 and a temperature of 29 °C (84 °F) (this is the upper limit of the usual temperature range of waters where the species occurs).