Betta Fish is biting his tail off

Question
I have had my betta fish for a year and he has done really well.  He eats well, I change the water once every other week with non-chlorinated water, and he has had the same bowl and plant since I got him. He is in a 1/2 gallon size bowl.  My problem is that for the last 4 weeks he has been biting his tail off.  I have seen him chasing his tail (just like a dog does!) quite often.  Why is he doing this and will his tail grow back?  Is there anything I can do to stop this behavior?  Thank you very much!!

Answer
Hi Janne;

I have heard of them doing this before. He is pretty old now so he may be getting a bit senile. They live to be 2 or 3 years old and are almost a year old when we buy them. Yours is about 2 now. This makes him a senior citizen.

He might be bored as well and needs some distraction. His tail looks like another betta to him. Prop a small mirror next to his tank and he will see his reflection. This will be the "other betta" now instead of his tail. It will give him exercise and keep him busy.

You might want to change his water every week instead of every other week. As they age, their immune systems aren't as strong. This means they are prone to illness more easily. More frequent water changes helps them with that.

Followups welcome

At Your Service;
Chris Robbins

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