Congo Colouring

[MermaidMel]

Hiya does anyone know about the changing colours of a male, because I have 4/5 males, about 2 inches each and 2 of them are a lot more silvery in colour (but def males, as I have females and kept them a long time and know the diff), all are perfectly healthy but the fatter (deeper) males are less deep in colour, do their colours fade with age?

 

[ian]

apparently the colour get better with age.