Holy crap nadus...my xingu II's really DID mature faster than yours...what the heck? Mine are already starting to go through their second color change! I think some of them might actually be in their adult colors...i believe I have two males and one female. I need to get lighter colored sand in there cuz the dark sand makes their colors darker so you can't see their kewl patterns as well. Makes the cobras patterns AWESOME though...so crisp...you should put yours on darker sand! haha