Yellow Stripe on Apisto

[LosC]

In the pic you can see the yellow by his eye and some spots further right. The yellow has filled in and now is a thick stripe. What is this a sign of? I moved him from a peaceful 20g into my 30g which is home to a few female rams and small peaceful fish. The Apisto is active and has taken over a driftwood cave that was home to the most dominant female ram. The rams are less active now, some less then others. My balloon ram seems to be the least active of them all. Can someone interpret my Rams behaviour?

[Dave66]

The color is a sign of maturity. Just like their larger cousins, Apisto males get more and deeper color as they age.
And the behavior is due to the introduction of a new male fish. They'll work out politics genially, but the dynamic won't be the same as it was before the male was introduced.

Dave