Paradise fish / Chinese bettas belong to the category of labyrinth fish and are considered easy to breed in this category.
For a successful breeding there are some important points to consider, which will be discussed here.
The willingness to reproduce depends mainly on two factors, namely the
- Temperature and
- Lighting duration.
Conditions necessary for breeding
A pair of Paradise Fish should be placed in a separate tank for breeding purposes. This must provide sufficient space so that males and females can withdraw. An increase in water temperature triggers the readiness to spawn. The optimum temperature is between 23 and 28 degrees Celsius.
The courtship behavior of the paradise fish
If the water temperature is right and the paradise fish are in a spawning mood, they become aggressive. The male starts to produce air bubbles and builds a so-called foam nest on the water surface. Conspecifics are unwanted during this time and are fought. A female ready to spawn may only approach if she encourages the male to build the foam nest. To do this, she checks the nest again and again, thereby indicating her willingness to mate.
The spawning behaviour
As soon as the male has built an optimal looking foam nest, the female spawns in it. This already happens at temperatures from 20 to 22 degrees Celsius. Living in an aquarium, paradise fish are practically always in the mood to spawn. In this mood they can hardly be socialized. The female becomes rounder in the spawning phase, especially in the abdominal area. It can produce up to 500 eggs per spawning season.
Breeding care and feeding
In the breeding care of the paradise fish the roles are clearly distributed. The male looks after the nest while the female defends the entire territory. Paradise fish live in faithful partnerships. The decisive factor for successful breeding is sufficient space. A pair can easily claim a 300 litre aquarium for themselves and not tolerate any conspecifics. The female supervises the male in brood care and intervenes if there is not enough foam left or a larvae disappears. If something happens to the male during brood care, the female continues to care for the nest.
The rearing of the young fish
Young paradise fish thrive best in a rearing tank with a water level between 10 and 15 centimetres. The low level ensures that sufficient oxygen from the water surface is available in the entire tank. Gravel or sand are suitable as the bottom of the tank and offer plants the opportunity to settle. It is advisable not to transfer all larvae from the foam nest to the rearing aquarium in order to improve the starting conditions for the individual paradise fish larvae.
Once they have used up the yolk sac, they need food. In the initial phase they only eat
- floating unicellular organisms such as paramecia and
- stuck single-celled organisms like bell-shaped animals.
]Alternatively, infusoria, i.e. microorganisms from the specialized aquarium trade, serve as food for the young fish of paradise. The temperature in the aquarium is important for breeding. This should be kept low to ensure that the fish grow slowly and can develop a strong body. If the water is too warm, a too early fin growth is initiated. The Paradise fish then tend to dwarf growth.