Change of colors

[Notone]

I have a male Betta fish, his name is 'Jergens' and when I bought him his colors where a weird and beautiful mix (white, red, turquoise and black). He look like a splash of watercolor, honestly. But then he got sick and started loosing his pigmentation, his fins looked bit off, as if he did it himself or on purpose he slash them by roughly swimming against the rocks or something. I treated him for at least 7-8 days and he started getting better, but still his pigmentation was off. Which I assumed was normal since he just got off the hook. But after two weeks of being re-introduced to his community his colors spiked again, but differently. He no is black with flashing blues, now. He looks beautiful, but I don't know what happened. I seriously don't want to blame it on the mutation these guys get sometimes, because is nothing as drastic. Nonetheless, is still fascinating and I wanted know if someone has gone through this, that can have some kind of explanation.

 

[NickAu]

Sounds like he has marble genes.

I treated him for at least 7-8 days and he started getting better,

You treated him for what? With what?