How do you tell if a Betta fish is male or female? Most of the Betta fish you will see in a pet store are males. There should be a sign that indicates this, or at the very least, the females (if there are any) should have the word “female” marked on their containers. If not, please ask someone who works in that department. To be sure, it is best to ask the pet store owner or general manager if it is a big chain store with a pet department.

You can tell by looking at them usually since the Betta breeders should only send Bettas who are old enough to be adopted. It depends on their age and their individual characteristics, though, but the males should have bigger finnage. The fins of the male Betta fish should be longer and have more flowing tails and fins than their smaller female friends.

In addition to having smaller fins and tails, the female Betta fishes are usually less bright in color, also. The females are normally tiny, light-colored petite little fragile fish.

Of course, remember to never put a male Betta fish with female Betta fish. Unless, you have studied how to mate them, you will end up with a tragedy on your hands. The male Betta will probably kill your girl.

It is possible to put a few female Betta fish together, but you have to give them enough space and hiding places. You cannot put more than 4 female Betta fish together in a 10 gallon aquarium. If you do, they will fight and end up sick and injured and possibly dead. With four girls, it’s possible that they may nip at each other a little at first, and then settle on a pecking order so there will be peace in the fish tank. You will need to observe them closely at first, though, and be prepared to separate them each into her own tank if necessary.

In short, it is better to give even the female Betta fish, as you do with the male Betta fish, her own aquarium. They do love to see each other, though, so it is beneficial to their health to set their fish tanks next to each other so they can play together and stimulate one another’s urge to interact from a safe distance - that is, with a clear glass or plastic wall between them!