Tiger barb colourations

[rvm]

I have 4 tiger barbs. 2 of them are standard black and white ones, one is an albino, and the other is green. The 2 black and whites have, over the last 2 or 3 days, started to develop a black band between two of their stripes. Is this normal as the get older, or should I be concerned. They are fully grown fish (about 3 inches)

 

[Tempestuousfury]

Are all of the bands (new ones) parallel to the existing stripes? This new stripe might be a sign that they want to breed, but I'm not sure... TAMHAYGFMU (That's As Much Help As You'll Get From Me, Unfortunately).

 

[rvm]

it's actually a mark running perpendicular to the other stirpes running between the stripe running up from the anal fin to the next stripe towards their heads. I'll try and get some pictures later!

 

[Lateral Line]

The genetics of farmed Tiger Barbs is now so messed up, you cannot guarantee an original B. tetrazona does not carry genetic faults. I don't think your fish are sick if that was your worry.

The "Green" Tiger barb was bred by selecting normally coloured fish that had "faulty" odd dark scales, by continually breeding the darker and darker fish, the green was produced. However, they all now interbreed and there are inevitable intermediates and throw backs.