The key to fish breeding

Few aquarium enthusiasts do not take their passion as far as seeking the breeding of their fish.
It is often even a major part of their motivation.

The ease depends greatly on the species.

 

For example, with livebearers, the willingness of the females is not required and it is enough that the male is persistent and skillful enough for the female, despite herself, to give birth about a month later to well-formed fry (platy variatus: hardy fish in aquarium).

But, in the case of egg-layers, which represent the vast majority of species, the fish of both sexes must perform a courtship and a voluntary act that leads to spawning.

Fish that do not feel the urge to reproduce therefore do not reproduce.

The factors that trigger this spawning are numerous, and some are probably still unknown to us.

 

All the aquarium books I have read since childhood speak of a "conditioning" phase lasting from one to several weeks.

During this period, it is always advised to ensure that your fish (sometimes, the sexes are separated during this time) are better fed than usual, with the best quality food available: "live" food, that is, the same as what they consume in the wild (fish happiness and animal welfare).

 

Indeed, it is observed that wild fish tend to spawn exactly during periods when food becomes more abundant. For us, this is in spring, with the sudden explosion in the number of daphnia and plankton (can fish safely eat tubifex?).

Elsewhere, these are different periods, but always following a local event producing an abundance of small prey.

This is how ecosystems balance themselves: the sudden prolificacy of a prey causes that of its predator, which feeds on it and thus reduces the excess.

 

The abundance of small prey "conditions" the fish. It first allows them to build up body reserves and energy to face the costly act of reproduction.
Also, natural selection has favored individuals who "knew" to spawn when the fry would benefit from a great abundance of tiny creatures. Species have thus synchronized to these criteria.

Aquarium fish obviously do not escape this great law of life (otherwise, they would have disappeared long ago).

 

The most experienced aquarium keepers, when they want to breed a species known to be difficult, never skip this conditioning phase. The goal is to trigger in the fish the deep reflex linked to feeding.

The most suitable small prey, if we forget the brine shrimps which are primarily sea shrimps and thus saltwater creatures, are probably Tubifex worms or daphnia (putting an end to the goldfish indoors).

But these miracle invertebrates are not always available when desired.

 

On the other hand, nothing is simpler than to raise Grindal worms or enchytraeids (larger), which are thus available all year round in unlimited quantities.
Contrary to an old misconception probably due to their color, these foods are not fatty and can be given daily. Modern analyses have shown their richness in proteins, and they are extremely appetizing worms for fish (the phenomenon of fishless aquariums).

They love them and Grindal worms, for example, have a size suitable for all species.

These are prey that fish seek in nature near the banks, where the surface meets the humus of the shores, precisely when the water rises, triggering fish reproduction.

 

Well-fed fish, with food matching the factors triggering spawning, in water whose temperature rises slightly (what temperature for an aquarium?), spawn much more willingly.

And often early in the morning, if the sun reaches them through a window (aquarium: which volume to choose?).

Nature is inimitable!

To better understand the sleep rhythm of fish and their well-being (fish sleep: do they sleep?), as well as common mistakes related to goldfish (the goldfish scandal), do not hesitate to consult these articles.