Interesting..

[bobbysgrl]

Do bettas change color when they are stressed? My fish seems to have black and yellow horizontal lines when she's less active and usually she is blue, purple, and red.

[herefishy]

Many animals, including fish display "fright" and "stress" patterns when in those situations, Fish included. Many fish will lose they color or intensity when either stressed or frightened. Betta females are no execption. What you are witnessing is one of the true marvels of nature.

[bobbysgrl]

That is actually quite amazing. Although it is not to great because she is stressed, it is amazing because of the change in colors. I am marveled.