My azul had very pronounced black bars in my 180g with black substrate. In my 450g he is pale, with light black bars. IMO, he looked better in my 180g. My temX has a lighter color green with better gold in my 450g, while he was too dark to show these colors in my 180g with black substrate. That is my EXPERIENCE, not just opinion, with cichla and dark substrate.
My experience with other fish, psittacus and dats specifically, has shown me that for them especially, the lighter the substrate the better.
Mjuniorc... I'm not steering him the wrong direction, I'm just trying to show him from my experience that the absolute type statements you're making are not always true. And me saying that darker substrate can sometimes darken the brighter colors of your pbass isn't something negative, it's just the truth as I have come to see it through my own experience. I'm not trying to say you or anyone else is wrong about anything. Just because I have a different opinion due to my experience doesn't mean that I'm trying to prove you wrong. And like I said, I don't like making absolute/blanket type statements regarding any kind of fish in most circumstances. This one included. It may make your fish look better even most of the time, but not ALL THE TIME.