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 ... and are a dull gray, green, olive, or brown. Before mating, the male spends hours blowing bubbles at the water’s surface to build ...

For example, stress can temporarily make your betta fish look duller ... of special parts at the edges. This reef fish flips between yellow, blue-green, and pink and usually looks pinkish-blue ...