Bubble nest

[1] Aphrophils include gouramis (including Betta species) and the synbranchid eel Monopterus alba in Asia, Microctenopoma (Anabantidae), Polycentropsis (Nandidae), and Hepsetus odoe (the only member of Hepsetidae) in Africa, and callichthyines and the electric eel in South America.

[1] Most, if not all, fish that construct floating bubble nests live in tropical, oxygen-depleted standing waters.

The nests are constructed as a place for fertilized eggs to be deposited while incubating and guarded by one or both parents (usually solely the male) until the fry hatch.

Water in these areas is often differentiated by having a higher temperature, lower salinity, oxygen level and alkalinity (e.g.

[citation needed] The nests are built by the male (sometimes females) and their size, position and shape depends on the species.

[citation needed] They are often built near an object that breaks the surface of the water, which forms a base for the nest.

The newly hatched fry will then be tended by the parent fish until they are independent, which can take from a day to several weeks depending on the species.