Bettas, like other most fish, amphibians, lizards, and snakes are indeterminate growers. Until something, disease, a predator, or old age-takes them down, they continue to grow their whole lives. The law of the jungle, so to speak, is what keeps them from getting huge.. most animals are eaten or killed before they get really big. Also, the longer an animal lives the greater the chance it might catch some deadly disease.
With all of that said, there is no way to determine a fish's age by just looking at it on the outside.
There are age signs.. slowly losing color, a "hump" back- my old one looks like a sockeye salmon.. but I don't count those as sure signs, some don't change much or at all when older.
If you had a microscope and were willing to kill the fish you could cut a cross section out of the otolith (a part of the inner ear) with a special saw (low speed diamond blade) and then count the rings under a microscope.
Otherwise, it's a guessing game.. normally they are between 2-3 months of age when you purchase them from the average pet store. They are at their "prime" at 3 months of age, their fins are fully developed at age 7 months, and their life spans run average of 2-5 years.
With all of that said, there is no way to determine a fish's age by just looking at it on the outside.
There are age signs.. slowly losing color, a "hump" back- my old one looks like a sockeye salmon.. but I don't count those as sure signs, some don't change much or at all when older.
If you had a microscope and were willing to kill the fish you could cut a cross section out of the otolith (a part of the inner ear) with a special saw (low speed diamond blade) and then count the rings under a microscope.
Otherwise, it's a guessing game.. normally they are between 2-3 months of age when you purchase them from the average pet store. They are at their "prime" at 3 months of age, their fins are fully developed at age 7 months, and their life spans run average of 2-5 years.
.. some of the bones in some fish have rings.. such as tree rings. During winter the rings get dark, and you use those darker rings to count the years.
