Originally Posted by Sowman
By the way, what do you mean that he is going to "marble". I am new to bettas so I don't know all the terminology.
'Marble' is a color gene, bettas that have this gene tend to change color over time, to put it simply.
For example, the colored patches on this guy will likely get better and darker as time goes on until he turns a nice Blueish Green; then he'll start lightening up again probably with some white patches coming though I'd guess.
Marbles are quite fascinating to watch; you never really know how/when they'll change ;)