Betta fish are incredibly popular ... Rainbowfish come in a slew of colors, including the blue-green-white gradient of the Lake Kutubu rainbowfish. They can reach 4.8 inches (12 centimeters ...

What is a betta fish? Betta fish—also known as Siamese fighting fish—are among the oldest species of domesticated fish. Their scientific name, Betta splendens, combines two languages ...