Melanotaenia Lacustris--Odd Colour Change

[nyx2k]

my 3 lake kutubu male rainbows have a noticeable gold stripe going from their nose and over their heads about 1 cm long.
they are juveniles and are kept with 3 females of the same age.
the females have not changed colour.
i only noticed the gold stripe when i added live plants a few days ago and this morning all the rainbows are showing a darker blue aswell.

i this normal?

 

[CentrarchidFan]

my 3 lake kutubu male rainbows have a noticeable gold stripe going from their nose and over their heads about 1 cm long.
they are juveniles and are kept with 3 females of the same age.
the females have not changed colour.
i only noticed the gold stripe when i added live plants a few days ago and this morning all the rainbows are showing a darker blue aswell.

i this normal?

The stripe is normal for healthy males displaying to females, as is darker coloration. I expect your fish appreciated the addition of the plants. I keep a dozen of these fish together in an equal mix of males and females. The males can turn this stripe on or off instantly like a neon sign. My males adopt a head-down posture while displaying the stripe and tremble in a effort to entice the females. It makes for an interesting display.

 

[nyx2k]

now you mention it the males are swimming with their heads down slightly.
the stripe comes and goes and so does the intensity of thier blue colouring

 

[trojannemo]

that's just telling you your boys have reached puberty. every time you see them flashing they're either trying to spawn or trying to establish dominance with another male. if they also shake near a female, then they're def. trying to spawn. enjoy your rainbows

 

[nyx2k]

they are very pretty fish and are displaying beutifully.
i really want some bosemamis but ive only got room for 2 not a biiger shoal so after getting a bigger tank last month it looks like i'll get another larger tank next month