The male carries the eggs in a brood pouch on his lower abdomen. After courtship the pair come close together so that the female's oviduct is close to, if not resting on, the brood pouch of the male, and the female expels some eggs into the pouch. This happens several times until spawning is complete. The male then wiggles about, as if to rearrange the eggs within his pouch. The exact point at which fertilization takes place is not known, though many assume that it occurs while the eggs are in the pouch. The incubation period is generally four to five weeks. To "give birth" the male bends forwards and then backwards, thrusting his pouch forward expelling one or two youngsters with explosive force. Raising the fry in an aquarium is difficult, as they require a large amount of minuscule live food