[4] Body color and fin length are important characteristics during courtship and mating in the breeding seasons where larger males are more likely to control better quality territory and have more access to food.

[8] A study by Estivals et al. (2020) in the Peruvian Amazon showed at least three separate genotypic clusters and estimated that the Apistogramma agassizii designation actually holds "tens of species".

As a result, they propose that Apistogramma agassizii no longer be considered a single, widespread taxon, but rather a mosaic of species with distinct, but still unknown, geographical distribution.

Just like all dwarf cichlids, Apistogramma agassizii requires weekly partial water changes in order to keep the nitrate levels as low as possible.

In order to reduce problems arising from their territorial nature, it is important to break up lines of sight within the aquarium, something that can be achieved with bogwood, root ornaments and hardy plants.

[2] Apistogramma agassizii is also highly sensitive to copper exposure, an increasing concern due to growing metal contamination in the Amazon.