Betta fish: who is it?

Betta fish enjoy live prey (bloodworms, brine shrimp, etc.). You can also feed them dehydrated or frozen larvae. The diet of these fish species should consist of at least 40% proteins.

The betta fish likes meals served at fixed times, generally one in the morning and one in the evening, but habits may vary from one animal to another. Be careful not to overfeed them! Some animals don't regulate themselves and will eat everything you give them, but that's not good for their health.
Be sure to clean the water of food waste. If it spits out its food, it may mean the pellets are too big for it. You will need to cut them in half. If that doesn't solve the problem, change brands or types of food.

You can make mealtime a moment of play and bonding with your betta fish. For example, play with a straw from which the food comes out. Once accustomed, your fish will follow the straw as a toy.

And company?

Be sure to research thoroughly before choosing a companion for your betta fish. Indeed, it is a solitary, territorial, and aggressive fish towards other fish, and even snails, which it might attack and eat. A male betta cannot cohabit with another male, as they will fight and one will die. Females should live alone or in groups of more than 5. The aquarium should be sufficiently large and provide plenty of hiding spots. If you only take 2 females, one will be bullied: to be avoided! It is very challenging to cohabitate a male and female betta, thus making breeding very delicate.
Also to be avoided:

Very colorful fish (like a guppy) or fish with long fins (like a goldfish). Your betta might mistake this flashy fish for another betta and thus a rival.
Other aggressive fish or fish that like to nip at others' fins, such as barbs.

Danios, Loaches, Platies, and Corydoras are generally wise choices. It's imperative to seek advice in a pet store.

The owner/fish relationship: it exists!

Betta fish are animals that can recognize several people and with which it's possible to build a strong bond. They are very curious and will enjoy your company. You can play with them by moving your fingers along the aquarium glass. However, never tap on the glass as it would make your fish very nervous.
When a male betta is happy, it often creates a "bubble nest"! A good way to know your companion's mood!
When you know your betta well, you can gently pet it, but this gesture should remain exceptional, as you may damage the mucus layer secreted by your fish on its scales.

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Les nageoires de mon combattant se déchirent, que faire ?

And company?

Be sure to research thoroughly before choosing a companion for your betta fish. Indeed, it is a solitary, territorial, and aggressive fish towards other water fish, and even snails, which it might attack and eat. A male betta cannot cohabit with another male, as they will fight and one will die. Females should live alone or in groups of more than 5. The aquarium should be sufficiently large and provide plenty of hiding spots. If you only take 2 females, one will be bullied: to be avoided! It is very challenging to cohabitate a male and female betta, thus making breeding very delicate.
Also to be avoided:

Very colorful fish (like a guppy) or fish with long fins (like a goldfish). Your betta might mistake this flashy fish for another betta and thus a rival.
Other aggressive fish or fish that like to nip at others' fins, such as barbs.

Danios, Loaches, Platies, and Corydoras are generally wise choices. It's imperative to seek advice in a pet store.