The long awaited event will be preceded with a change in the behavior of one or both  of the pairs, although the male is commonly the first to be observed with a change in behavior. This may be increased swimming in the vicinity of the spawning site, active cleaning of the spawning site, moving of substrate and rocks (it is amazing how such a small finish can manage to move a sizable rock to the other side of the tank!), nipping at fins and chasing.

The female will become more full in the abdomen and the ovipositor will become extended and visible (a tube through which eggs are moved from the body (deposited) to the spawning site located adjacent to the anus.  Egg laying has been reported happening at all times of the day and some have indicated that it has occurred during darkness.  My experience that once a pair begins spawning with any regularity they will generally spawn at the same time of day each time.  The female lays the adhesive eggs on the selected surface/site and then the male fertilizes them.

Egg masses vary in size and quantity.  A. ocellaris may only lay 300 – 500 eggs per spawning whereas  P. biaculeatus  commonly lays 1500 – 2000 eggs!  Eggs are small slightly oval masses generally 1 – 2 mm in length.  Coloration is generally pink to orange, but may be yellow which may be indicative of a dietary deficiency in the adults’ diet.