how to determine a male fighting fish if its still a baby?

Answer 1

They don't usually develop sexual traits until about 3 months of age. If it's younger than that, you'll just have to wait a while. After that age simply go by the developing finnage. The size of the dorsal fin is often the first give away I see in mine.

Also: Bettas easily live over 5 years in many cases.
They are sexually mature before 6 months, often at 4 months they are ready to breed

Store bettas are usually less than 5 months of age.

Be careful, there is a lot of bad info and erroneous myths about bettas on the net.

MM

Answer 2

It is nearly impossible to sex at that young of an age for Bettas. With many of the mixed breeding of female bettas with the longer fin-age, it would be nearly impossible to determine the sex until it is almost matured, and even then it could be difficult. More information on what type of betta it is and if the mother had long fin-age or not would help. If you have several babies, you are basically going to have to scrutinize them, and look for the longer fin developing underneath on some and not others. That can help, but that is not any guarantee and no one can sex a betta until it is closer to maturity. You can't even go by the brighter coloring either, but it can help.

Answer 3

bettas only live for 3-4 years... so they grow very quickly.
they are sexually mature at 6 months old - they are close to 1.5 inches long at that time.
if you bought the fish from a petshop, it is almost definitely over 6 months old.
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