Multicolored double tail betta **you wouldn't keep a dog in a dirty cage all it's life....don't sentence your betta to a dirty "bowl" or "vase". They are tropical fish! They need room to swim and a heater to warm their water!**
Did you know there is a betta gene called "Marble" that causes them to change color throughout their lifetime? If you ever see a betta with splotches of color..it might be a marble! Keep him in warm water with plenty of room to swim and you will see your fish change colors and thrive!