There could be several reasons why a white betta fish turns black:
Marble Gene: If the betta fish's body contains marble genes such as blue, white, and black, it may change color at any time.
Fright: After being frightened, the betta fish may lose its color and become dull in black and white.
Old Age: As the betta fish gets older, its color may change, which is a normal physiological phenomenon.
How to Deal with the Situation of a Betta Fish Turning Black
If a betta fish turns black due to fright, the following measures can be taken:
Provide a Quiet Environment: Reduce external disturbances and provide a quiet and stable living environment for the betta fish.
Avoid Disturbing: Try to avoid walking in front of the fish tank or making noise to reduce the disturbance to the betta fish.
Observe the Condition: Pay close attention to the behavior and health status of the betta fish and handle any abnormalities in a timely manner.
Through the above methods, the betta fish can be helped to gradually regain its vivid colors.