Yeah, they have grown so fast maybe because of food and constant WC.Raj, thats a super nice setup. I love the sump! And your fish selection is what Id put in my new 180! Enjoy watching it grow!!!!
Light subs definitely affects coloration and lighting.Looking good. The light substrate is making your fish look very light.
I also have a 180g SA community, mostly cichlids, but it's different from yours. I like having a big oscar as the centerpiece.
I would watch that chocolate closely for aggression.